i have a TBAC Ultra 7 and couldnt be any happier. as was mentioned above, its extremely lightweight and works very well. i would caution you going too short more or less eliminates the idea for a suppressor, especially on a 30 cal. if you are going to put a few cans on the same form...then sure, get a shorty, mid size etc but if you are getting just one...i, personally, would not go for the shortest/lightest option based on that alone
