Hey all - I live in my van and with my Golden Retriever along for the journey need all the space I can get. I've used Yakima rocket boxes for years now with no problems whatsoever. I used the standard Yakima side mounts on my old 83.5 Westy and logged serious miles carrying kayaks and a fully loaded rocket box all over Baja, the West Coast, and Canada. Wind, snow, tractor trailors, rain, no cracks. However when I awoke to summer heat in Reno, NV a few years back and drove off from my urban campsite with TOP UP and ran into a drive-thru awning (you would think someone would have at least flashed their lights or waved - wouldn't you?) that was the end of that top. So I headed down to Sacramento - my uninsured home in dire condition - to hunt down a replacement and at the very last salvage yard I checked I get the old "should have been here last week before I rested a VW Bug on top of it" story. HOWEVER, upon inspection I saw some small fracture lines and the guy says that if I remove it he'll sell it for $150.00! What choice did I have? A large project, yet I found perfect canvas underneath, and soon had that top restored to better condition than my original. So can these tops bear a load? I think so! I eventually took that Westy off a Colorado cliff and she now lives in a Norwood, CO junk yard with plenty of good parts (ask for Therin). So on my latest '87 Westy, I used Yakima TOP loading mounts, large washers (don't use the cheap neoprene gaskets Yakima supplies in their kit), and longer than supplied stainless bolts. I sealed all bolt holes, and filed down bolt ends (canvas), and this things absolutely bomber. I'm a skier and commonly have five to six pairs of skis and gear in my rocket box - easily over 100 pounds. No leaks, no cracks. A few tips: Load heavy stuff in the rear of your box, get extra long bars so you have grip while standing on the rear seat to load/unload, use tall mounts so your roof vent will open completely (and easy cleaning), make sure you have a window or door open when popping your top, and ABSOLUTELY be sure all doors/windows/openings closed when lowering so you can use the air pressure as assistance. It also helps to be tall and strong! Good luck. Tom.