Thule v. Yakima - few topics bring about more angry debate. I've had my Thule system for about 5 years. I've hauled mountain bikes, skis, and three kayaks on my roof. It has worked flawlessly, albeit noisily. Yes, Yakima fans, the support bars will probably bend if you put three kayaks on them regularly. But if you are hauling that much weight with any frequency, you need a trailer, not a roof top rack system. Normal mortals won't have problems with bicycles, surf/whitewater kayaks, or one touring boat with an occasional second.
Less physically strong riders may find its heft a bit much. There are wheels to roll it on flat surfaces, but you wouldn't want to carry it very far. It locks securely to your tow hitch and carries up to three bikes. The bikes are held in place with ratchet straps round the bottom of the wheels and a clamp for the top tube or, for carbon bikes, one of Thule's 982 frame adapters.
The most likely causes of excessive wobble at speed on a motorway are either that you have not placed the arm clamp sufficiently close to the chainring OR you have not tightened the clamp sufficiently. Having said that, there is a further cause where the clamp can slip UP the frame IF your frame gets thinner in that direction (eg My Cervelo S3 does precisely that). In that scenario you will need to put the arm clamp slightly further away from the chainrings at a thinner part of the frame.
Most off-road fanatics will agree that you can never have too much space to pack your gear, and a rough-and-tumble roof basket — like this offering from Go Rhino — is a great solution for Jeep and SUV enthusiasts looking to venture well off the beaten path. This rack is great for strapping down anything from spare fuel to camping gear, and includes additional LED lighting to brighten up camp after sundown.
I own and use two Thule 815 Kayak Cradles that were purchased from Dick's Sporting Goods (DSG). Interestingly, there is no information about them on Thule's website. Apparently, the 815 is made to DSG's specifications. One I bought used off of eBay for $75 plus $13.25 shipping. According to the seller, it was used for three seasons before I got it. The other I just bought at DSG for $79.99 ($99.99 less a $20 off coupon) plus $4.80 tax. The box indicates that it was manufactured this year.