Think you have to ask yourself: regardless of research and benefits, what can this product actually offer you and is it significant? What is missing from you now that you're not getting from your current clothes?
Do you need said cardiovascular benefit? Are you an elite runner chasing that .1% edge on the competition or do you have more to gain by mentally pushing yourself harder alone / adopting performance increases that don't cost you money.
I apply similar logic to supplements. People buy so much shit - wow, like 8 different supplements - to do all manner of things to their body, the benefits of which they aren't really even sure of...or if they've even been proven to work...and they are nowhere near the level where they should be looking for an edge. When someone weaker than me talks about their psyllium husk and flaxseed oil and BCAAs...I just think wow, what a waste of money; this person hasn't even pushed the limits of what they're capable of without this shit; I'm not even that strong by powerlifter standards and this person is taking all this shit while all I do is supplement protein (if I don't eat enough meat).
So honestly, unless they prevent heart attacks or make you perform significantly better and you're already at your limits, I'd rather you be buying them for the muppet look. And if you tell me it's to stay warmer I will tell you to run harder/faster/further!