I've been spending more and more time in the garage (the weights and treadmill are in there now).

It's a 2 car garage, and I typically only park one car in there.

I want to put down some kind of flooring so it's more "inhabitable" feeling.

I think I want to go with the flexible floor tiles. Something I won't panic if spill some oil, but doesn't seem as cold and dark as unfinished concrete.

Anybody have any input on these?

I have looked to do something similar. It appears a stall mat (like for a horse) might be a cost-effective way to get it done. It might have a heavy rubbery smell for a while. Still a few hundred bucks depending on the size you are looking for.

I am having trouble sourcing locally. YMMV

I actually have stall mats that I use for my weightlifting equipment. They did smell, but that was gone after a few weeks.

I think I'd rather have something a little "nicer" than stall mats for the main flooring. There are a plethora of vinyl/pvc type options for $2ish/foot.

Have you looked into something like Racedeck ?