I would caution AGAINST the low profile Troys on a standard AR flat top. The AR sight height was chosen for a reason, and that reason was NOT to accommodate a carrying handle. They are the height they are because of the straight-in-line barrel/recoil system/stock. The carrying handle was just added since they already had the sights up high where they needed to be.
Take a look at this thread, especially look at pictures of the prototype AR-10 rifles and other historic rifles that have straighline stocks/recoil systems:http://www.m4carbine.net/showthread.php?t=66902
1. Eugene Stoner chose the straight-line recoil system for it's simplicity and its muzzle rise reducing capability
2. He designed the stock around the recoil/buffer system.
3. He then put the sights at the correct ergonomic height to account for a straight stock.
4. The carry handle was then added in order to protect the sights AND the originally top-mounted charging handle.
Don't put the cart before the horse.
Edited to add: The Troy Micro sights were designed for guns like the HK416, which has a higher Picatinny rail than a standard AR/M4/M16 in order to accommodate it's piston system.