Advice on purchasing new O2 sensor

Hey folks,
so my cat was stolen (sad violin chords), I ordered a replacement but it doesn't come with the downstream o2 sensor. I'm looking on partsgeek (too new to post a link still) and having trouble understanding the difference between these two parts:

Part 1, $55:
Denso Oxygen Sensor - Downstream
Part Number: 18435-05051655
Notes: OE Style -- DENSO is the O.E. Manufacturer / Oxygen Sensor
Features:

• Designed to detect the amount of oxygen in the exhaust system
• Constructed from high quality material
• Features double protection layer, aluminum oxide trap layer, PTFE filter and stainless steel housing
• Manufactured with precision to meet OE standards
• Easy installation

Part 2, $39:
Denso Oxygen Sensor - Downstream
Part Number: 18435-05051629
Notes: Universal -- O.E. Quality Universal Replacement Sensor
Features:

• Manufactured to the highest O.E. quality, guaranteed to fit right
• Aluminum oxide trap, this extra layer helps to protect from silicone and lead poisoning
• Stainless steel housing and porous Teflon filter all contribute to make a long life
• Improved engine performance and greater fuel efficiency
• Prevents premature sensor failure

I saw the cheaper one mentioned something about soldering it in place, while the first one includes a picture of what looks like a custom electrical connection, so I'm guessing the more expensive one is plug-and-play, and the "universal" one I'd have to splice. Can anyone confirm my thoughts here, or tell me what the difference is if not that?

Thanks for your time!