After reading all the opinions here on flat top vs A2 or A1 uppers, I built up a flat top upper.
I went with a detach carry handle like you are talking about, and I like the feel and sight.
However, that handle is heavy, close to a pound.
Plus, I really feel the AR series rifle is a true carbine, not a long range rifle. It really shines with iron sights and when the small peep is zeroed at 200 yds.
Because of this, I am now looking to dump my flat top and am looking for an A1 receiver without the bump on the side.
What the carry handle will do for you is give you a standard M16/AR-15 rear sight with a familiar profile to those who trained on the A2 uppers.
Get one, and see if you like it, you can always sell it on the EE board and recover much of your investment. Just make sure you buy a good quality carry handle, Colt, Bushmaster, etc. Stay away from the cheap junk.