Thin, not as hot to wear Leafy suits, or mesh ghillie suits, they work amazingly well. Biggest thing is to cover your stands-out like a sore-thumb pink skin of face and hands. (And now some of us have white hairs all over our faces too HA!) And movement when not in the shade? Stands out super bad. Also remember to think about your watch! If not covered-up by your sleeve.... that sunlight reflecting off the face of the watch when you're manipulating the remote for an eCaller (AND the sunlight possibly reflecting off the glass of the remote itself).
When I'm going into a new area and I don't know the coloration I'll find, I tend to use my Natural Gear camo pants, that's based more on greys and such (and bring both of the mesh ghillies, since they're so lightweight). Then after I've been there and know whether a Woodland coloration or a Desert coloration would be better, then I'll change up accordingly.
My favorite piece of gear? My leafy boonie hat! It's the lightest and most comfortable and best at letting the heat out and not cooking my head. I've even had a small bird land upon my head while wearing that leafy boonie last year during deer season! The way it changes the recognizable shape of your head is invaluable.
When I'm all done up in the leafy, I routinely get hummingbirds curiously investigating "this bush" inches from my face!
After 45 minutes of holding my rifle at the ready on this narrow POV while on this one set for Bobcat... I began to stand up (in full leafyu) and realize Oh Snap! There's a Bobcat right there 8yds away! Thankfully I froze mid-standup, then slowly raised the rest of the way to standing. He was laying upon the ground focused on the decoy, eyes slightly obscured by low-lying rabbit brush, so he totally didn't see me. Even after he caught my scent in the air and looked around for me. He saw "this bush" standing there (frozen still of course) and he took a long time of staring at it before he finally decided he didn't trust it.
With the mesh ghillie, I had a cottontail 18" from my right foot before when the wind was right! And... later on I shot that rabbit.. he's laying dead at my feet... as I continue to focus on this one area in front of me. Then I turn my head to look over my shoulder to scan around me and I'm like "Oh Hello!" a doe, maybe 25yds away! She feeds and nibbles until she finally gets behind me and catches my wind and smells that freshly killed rabbit and she books it pronto!
If you're going into a Desert Arid landscape... the Kill suit Mesh Ghillie they sell on allpredatorcalls.com is AWESOME! But with the strips of mesh... you'll need to check if bringing your weapon to bear will want to catch on the strips. I'm in Kommiefornia and so I have to use the very "Bruno" Thorsden customs stock for my AR... when using that AR I can't use the mesh suits because the way the butt of the stock is, it'll want to catch and tangle the strips some times. There's ways around it, such as making sure the weapon is being held at the ready above these garments on your underarm and side area of the body. But that's kind of a PITA to have to do.
Big thing is always remember to back yourself up into some shade whenever possible. Get all settled in and comfortable to where you've stopped being fidgety... before you begin calling. Also have your shooting rest setup already such that it's height puts your crosshairs able to easily be drawn upon your caller or decoy before you even begin calling, to make sure you're already ready when the opportunity comes.