I purchased a Baronette Big Jim 275 blind last year specifically for turkeys. The blind is 80" tall inside so it has plenty of upper limb tip room. I went through every blind spec I could find and went inside every blind I could to gauge window height. As with every commercial hub-style pop-up, window height seems a bit high so that is an important consideration. I ended up stringing a bungee cord from the outside of the blind, through the window and hooked it to the rods inside the blind in order to pull the bottom of the window down. Before I figured that out, I put my first practice shot from the blind through the edge of the folded down window fabric. With the bungees, I am able to have enough clearance. I do not shoot through the mesh, just open the inside window fabric and adjust the mesh to allow for small shooting holes. Turkeys will flat ignore a blind, even if it's in the middle of a field. I hunted once with another guy, he killed a bird and we layed it RIGHT NEXT to the blind on the outside. Two Jakes came in later, saw the bird and immediately ran over and stood on top of it mere inches from the blind window. We were mouth yelping and mouth gobbling and they were gobbling back. Lemme tell ya, gobbles are a lot louder when you are 1 foot from the gobbling bird! I have tape-video to prove it, too! Yes, those were jakes but I have not had a turkey spook just at the sight of the blind.
Turkeys spook at movement so the blind blocks their eyes from movement. Tip: Get a blind that is black on the inside, then wear black while you are in the blind so the birds won't see you, just be careful to close the windows on the back side or the birds will catch your silhouette. Some folks hunt them from natural ground blinds but I don't have the sit-still-itude for that! And pop-ups are a lot more portable and take seconds to put up so you can run-and-BOW 'em. Turkeys are preyed upon by birds from above and they have 270 degree vision so I can't imagine you'd be able to get a shot off from a treestand, unless you are one lucky dog. Inside a ground blind you can get away with alot of movement.
Best of Luck, Spring turkeys are a ball!
TomBow