I'm not familiar with US Tactical, got a link?
Ilike the FLC, my one complaint is lack of padded shoulder straps, but it also makes it easier to use a rucksack.
This is what my 3 Gun Rig rig consists of:
Vest:
Specialty Defense Systems Fighting Load Carrier
Thigh Rigs:
Safariland 6004 LH for Glock21
Tactical Tailor Modular Leg Pannel
Both were attached to my vest with 3 Gun Gear custom made MOLLE drop leg adapters (so they wouldn't drag down my pants like if they are attached to your pants belt)
Pouches on Vest:
2 Tactical Tailor tripple pistol pouches
2 Spec Ops Brand Double M16 pouches
2 Tactical Tailor Shot Shell pannels
1 Spec Ops Brand Quad M16 pouch (I used it for extra shot shells)
Pouches on Thigh Pannel:
2 Tactical Tailor Single Pistol Pouches
2 SDS Single M16 pouches.