Hi all, I need to replace my radiator and thermostat. 98K miles. So big question - should I get genuine OEM for both, or "OEM-equivalent" brand like Nissens, etc for radiator? For just the radiator assembly, difference in cost is about $250.
Thoughts?

Get an OEM-equivalent of a decent brand and your good to go. I've used NRF in the past

The dealership business model is profit made from service and parts, not car sales. That means they jack up the cost of each because that's where their highest profit is. To wit, OEM parts are ALWAYS overpriced. There's nothing wrong with aftermarket parts as long as you stay with a reputable brand.

+1 to @cooper48 There is some videos circulating about OEM parts, which are basically the cheapest version of an aftermarket part. Most aftermarket parts close to OEM price are actually higher quality. Check out Royalty Auto service on youtube regarding just oil filters, its mind opening!

Thermostat, Rein is great. Two years personally and no issues, a fellow forum member was having issues and switched to the rein which solved his issue instantly.
Rad, Nissens should be fine. Currently running the Nissens oil cooler and heater core without issue.

Happy motoring!

I have a nissens condenser and its fine. Old one was valeo.