Regarding AC: The 04/05 prius is much more efficient than most other cars. The compressor is continuously variable speed electric, so once cabin temp/humidity equilibirium has reached desired temp, it can run at just the right speed to maintain it. Cabin fan is also variable, though I am not sure if continuously variable. Because it is all electric, AC can still operate from HV battery without the ICE running. Most other cars, the compressor is driven mechanically, and is either all on, or all off. To regulate temperature, either the compressor has to cycle, or heat has to be added. So 28MPG is hogwash.
When the wind blows across the side of my Jetta, the car shakes pretty violently. It makes it seem to passengers like I, the driver, am steering erratically, but it's just the wind. So that sort of thing is something I'm already used to.
If you're used to that behavior from your Jetta then you shouldn't have any problem at all with the highway handling of a Prius.
Every car I've ever owned seems to have a different highway speet spot. My previous commuter (Mini Cooper S, 163 hp) cruised effortlessly at 80-85. In the Prius that sweet spot seems to be about 65 or 70. It can go faster, but it just doesn't seem all that happy about it - the engine seems to spent a lot of time revving pretty high. I've never had it above 80. Sounds like I'm in the minority here, but that's just my $0.02. When I want to go fast, I take the other car.
I rarely go over 80 unless I'm forced to... ie passing a complete moron. The fastest I've gone in my Prius is 86, I think, and that lasted about 60 seconds. The last thing I need is a stinking ticket!
I've gone over 100 a couple of times. The first was in eastern New Mexico on a lonely highway outside Roswell. I was just trying to see if I could go that fast. I backed off as soon as I hit 100. The other time I was racing another Prius (!) on the 5 in LA, in moderate traffic. In that case I wasn't paying attention to the speedometer. When I looked down I was going a couple of MPG over 100. I backed down and watched the other Prius pull away. I had pulled up behind him, challenged him by passing fairly briskly. At that point the race was on. It was a silver Prius with some hot rod style paint and decals.
I recently returned from a round trip to Key West, FL and the worst I could manage was slightly less than 40mpg by the MFD for one tank; incidently that's my worst tank ever for either the 2005 or my 2004 that I traded with about 25K miles. That was after playing cat and mouse with a cluster of cars doing 80-90 or more for several hundred miles; there may also have been a headwind but it was hard to tell. There seems to be a significant hit to mpg when you set the cruise control for higher than 75. When I got back to Virginia with it's lower speed limits and higher traffic the mpg improved to about 50.
I do a lot of highway driving at speeds of 70-75MPH, and have absolutely no complaints. The Prius handles and feels better than most vehicles I've driven. Keep in mind that as your speed increases, so does the wind resistance. This means decreased MPG unless you pull in about six feet behind a fast-moving semi. (Not recommended unless you're willing to lose about twelve feet off of the front of your Prius.) My highway average is usually around 46 MPG, not bad at all for going 75. Hills don't seem to affect this much - mileage drops on the way up, but the ride down is free. (Nearly.) Side winds do tend to push the Prius around a bit, but this feels much less pronounced than in a VW Beetle or Golf. I haven't driven a Jetta recently, so I can't comment on your situation. As for the "twitchy handling" at highway speeds, a topic of active debate elsewhere on the forum, I don't buy it. My personal theory is that the folks who are complaining about twitchiness have been driving a vehicle with sloppy power steering and a large dead spot. The Prius' power steering is very different from that of older cars, especially of American make, as it completely eliminates dead zone (or slack, or backlash - that is, the amount that you can turn the wheel from side to side without actually turning the wheels) AND it dynamically adjusts the amount of steer to compensate for increased speed. The result is a very easy, very intuitive driving feel. Anyone who has driven a VW, Audi, or BMW should feel comfortable with the Prius' steering. Those who are trading in their late-80's Buick are in for a (hopefully pleasant) surprise.
I test-drove a Prius today (albeit briefly) but the steering was much looser than on my Jetta. Frankly I don't know what everyone's smoking when they call it "twitchy"... they should try driving a Jetta. But while the Prius' steering is fairly loose, as xevious said, there wasn't actually any dead-zone, thankfully -- I hate that!
A gentle reminder: I just bought my Prius. I will take possession of it next week (My garage is rented out until the end of the month.) I've driven it about 40 miles. So, all I have is the owner's manual, which WARNS US not to drive over 85 MPH!!
Technically, the clearly-posted speed limit sign warned many of the folks in this thread (myself included) to not exceed 55, 65, or 70 MPH. As our posts will attest, we are, as a group, not likely to heed such safety warnings. During the break-in period, you shouldn't exceed 85. If you value your life, you certainly shouldn't exceed 85 on a regular basis. Or possibly ever. The Prius is electronically limited to slightly over 102 MPH; driving at such speeds will deplete your battery, thin your hair, and inflate your insurance premiums to an amount on a par with the national debt, but should not cause damage to the vehicle.
actually one of my good gripes, until i get a ticket, about this car is that i drive too fast. i used to have the HCH and man i drove slow b/c that car didn't feel like it could move. now w/this car i can't stop speeding.
When I brought my new car home from Helena I averaged 47 for the trip driving on I90 at 70 or 75 (Montana). No problem with stability, speed or anything. Got behind a Truck going about 60-65 going up over Lookout pass and passed him with out a problem on a steep grade and got up to speed. I would say the Prius is a good Highway car.
the limit of the prius is 108. that's just the gears top speed.. yes it's electronically limited but only by the limit on the electric motors. Could the prius go faster than 108? no.. even downhill.. no. it tops out there. fully agree with the break in period. good to post that again. i accidently did 90 on my first trip home from the dealer.. looked down.. oh 90.. let's slow down. it was just soo smooth.
The prius handles excellent at highway driving. I drove mine cross country with the cruise control set at 80mph and had no problems.
lol. i wonder what the car would do. with it's stability control and such i would think for it to stay ok for a tiny bit. then maybe crash horribly out of control. ah.. the golden question. which tire would blow at 90 mpg? each tire has a different effect.