Flexible rack
I have had the Thule rack system for several years and recently transfered it from my F150 to F350 truck. The process took about an hour and was fairly straight forward. I have three kayak racks mounted on the system and they do whistle in the tall position, but more from the kayak racks than the bars, which do have the rubber strips installed. My only complaint would there are only two positions for the racks and I think there should be third position, since the rack sits higher than it needs to be for long kayaks to clear the cab. Thule has addressed this, since I purchased my rack by offering different height racks. I still think a third position would be useful to allow a bit more cargo space in the pickup bed with the rack in an intermediate position.

I like the Thule system and I constantly get asked about it. I agree it would be easy to steal, so care needs to be taken about where you park your vehicle. All and all, I am very pleased with my Xsporter and the flexibility it offers.

Thule Xsporter 421/422
This is a great rack and I am very pleased with it! My only disappointment was it only had two adjustable positions where as other models have five positions. I cut additional slots in the uprights to allow three postions. One thing I did not consider when purchasing this rack is I have a tool box on the back of my truck which forces me to place the rack over the top of my wheel well and does not allow me to lower the rack as much as I would like. It's still a great rack and I recommend it highly! I have no trouble with whistling as some other reviewers wrote. The rack looks good on the truck also!

Hard to install-Far too easy to steal....
After having spent about 5 hours trying to finish putting this devil together I decided to stop and write this review.

Pros: It is pretty. It would be prettier if I could get the rubber strips to stay on, but after an hour of trying everything from sliding them to tucking them to hitting them with a rubber hammer, they continue to pop right out. The suggestion of just plugging the groove with duct tape is sounding better and better.

Cons: As someone else commented, it is SOOOO easy to steal. You might as well give 0 to a good charity and avoid supporting the theifs drug habit!! It comes off very easily and the locks only lock the uprights to the supports.

As noted by someone else, on my Tacoma, you can't use the lower position. I also had the problem someone else had of not being able to make the uprights vertical, causing the top rail to bow. I cured this by pitching the directions and puting the thing together on the ground with all bolts loose. I then lifted it on to the truck with the adapters hanging and made everything finger tight before grabbing my wrench. I then went bolt to bolt tightening each by only a few turns.

Since the other person who reported the above problem didn't have a Toyota I would assume that all the adapters pull the rack supports inward toward the bed so that they don't sit completely on top the bed rail. Tightening down too hard on the adapters can easily tilt the supports sidways unless the top bar is on. If you attempt to put it on with the adapters too tight, you get the bow.

Thule should have made the track on the Xsporter wider and provided a wider tongue with a longer neck on the adapter to allow it to sit fully on the top rail.

Note that the Toyota adapters you have to buy are less than the HALF the size of the sturdy looking ones that come with the rack. I struggled to get mine on for nearly an hour before I figured out that one of the adapters had its hole drilled at an angle. Make sure you test all the bolts in your adapters before trying to install to assure there are no defects.

I now have to wait for Thule to send me a replacement adapter, but that is not the worst of my problems. I travel frequently to the city and this rack is so easy to steal I fear leaving it at a rural boat launch much less an urban parking lot. All I can figure to do is cable lock it to my bed loops and hope no one has the tool needed to remove them.

Great Rack!!!
I bought the xsporter 422 for my 07 Tundra D-cab. I carry extension ladders, etc. on it with no problems and lower it during the weekends when not in use. A lot better looking than the weekender I had before, especially when there wasn't a ladder on there. If everyone would use the rubber inserts in the rails that are provided, there would be no whistling!! I bought my rack used so it didn't come with enough rubber stripping so I called Thule and had two 72" strips shipped for about 15 bucks! I marked on the rack where the bolts to the crossbar were, inserted the strip with the bolts in place, cutting a hole for the bolts to come through and mounting it to the uprights for a firmer fit and to make sure there was no rail exposer for the wind to catch. After putting the load stops where I wanted them, I cut the remaining strips to fill in the rest of the rail. Absolutely no whistling!!! I get a lot of attention with this rack. And it works great too. K.C.

Whistling Thule 421
If you have a 05+ Tacoma you should look for a different rack , TracRac is good choice. This rack will NOT go to the full lowered position with the shape of the Tacomas bed. Also if your using this for contractor needs and you add the "Load Stops" this rack will whistle like crazy! SO ANNOYING!! People will here you coming from miles away. Thule really dropped the ball on the R/D on this one.