In my very unlimited experience with compression I remain unconvinced. Socks - wore them post runs for a while for recovery and can't say they made any real difference to be honest. I didn't like wearing them anyway, reminding me of going to a school PE class and they kept falling down even though they were supposed to be, er, tight.
I accidently bought a compression top online in a sale - liked the look of it more than anything and bought a large. Usually a med-large, not a big guy and like looser tops in general. I was actually quite shocked at the sudden appearance of very distinct abs and pecs, well toned arms and deltoids and was frankly a little embarrassed. I'm 51 and British and didn't like the idea of my neighbours gossiping and questioning perhaps a middle age sexual identity crisis was looming. So I wear it as a thermal, as a layer, all reserved and low key, you know. Besides that, I couldn't breathe. And it's itchy. Always looking for cheaper alternatives, just buy something 4 sizes too small for you or wrap yourself up in cling film. Now that would get the neighbours talking.