Dude, those modded MacSports-style trolleys are legit for basecamp hauls-I’ve run a similar setup (stock Heavy Duty with 16″ puncture-resistant Schwalbe Marathon tires swapped in) on multi-day trips in the Cascades and it crushed 200lbs of group kit over rooty, 20% grades without flipping. Key mod I swear by: drop the tire pressure to 15-20 PSI for rocky singletrack; it conforms better than stock 30+ PSI and grips like velcro without ballooning on mud.
For thru-hikes, they’re dicey solo unless you’re ultralight-my 14lb Cnoc Outdoors Vagon (aluminum frame, smaller 10″ tires) clocks 100lb capacity collapsed to 24×12×8″ but snags less on switchbacks under 30″ wide. Reinforced it with Dyneema webbing straps and a pivot-lock hitch to kill sway. Alternative beast: the Ortlieb Trailer (connects to packs via aluminum arms, 8lbs empty, amphibious tires for creek crossings)-bombproof but pricier at $350.
Watch for axle fatigue on sharp granite; I gusseted mine with ⅛″ aluminum plates after 500 miles. Pics of your setup look killer-what’s your total loaded width on tight trails? Anyone pair these with e-bike batteries for hybrid pulls?