Switched to LT tires almost 3 years ago and the 5er in my sig and haven't looked back, and won't! Higher payload ratings and reputation was why. Love my GY G614s. And the OP is correct. Lay both tires side by side and look at the difference, then pick them up. Major differences. On my TT however, I have Maxxis 8008s on it and have WAY more capacity than the 4400 pound axles under it. When it is time for new ones, LTs will be it.
2012 Sandpiper 365SAQ weighing @ 15k, Onan, 2nd air, slide toppers, TST
2013 F350 6.7L Lariat 4x4 CC DRW,Viair 1007, Ride-Rites, Edge CTS, B&W
2001 Chevy 3500CC DRW 4x4, 8.1L, 4.10 gears w/ Detroit TrueTrac
2001 Ford Excursion Limited 4x4 7.3L,V/B Spring Mod, ProComps, Hellwig Swaybar, & other 'Necessities'