A Gen I with 175000 miles and an unknown battery replacement at 137000 at $4200 OR A Gen II with roughly half the miles and oroginal battery at twice the cost ???????????????
If you like to tinker and spend money on your car, buy the Gen1. If you want a hassle free car buy the Gen2. Pay now or pay later...Gen1's have a lot more issue$ (tranny, battery, inverter) as they get older and are harder to find used parts for ... and most dealers are bad at diagnosing Gen1 problems....they often sell stuff to the customer they don't need while trying to figure out the problem. Less goes wrong on Gen2s, more people familiar with them, and plenty of donor cars should you need used parts. I tell my friends they are financially better off with a 150k mile Gen2 than a 75k Gen1, although I personally like Gen1s (since I can fix them myself).
+1 on 3prong's advice. I have both. I prefer the Gen II but like the Gen I for city driving (better city mpg in the summer). The Gen I and II (IMO) drive very similiar but I can squeeze more mpg's out of the Gen I in the city (summer only). The Gen I has it's quirks too. It starts the ICE when you put it in park (not sure why). It takes longer to get to full hybrid mode when warming up (hence the mpg penalty in winter). The Gen I is not as roomy or comfortable as the II. Both are good cars though.