The ProRide meets requirement number three no problem and is no problem when left in situ. Thule do advise you take it off when not in use as it will affect your fuel consumption. But I found it to be negligible, happily staying around 62-64 mpg on long motorway drives. With a bike on it typically dropped to nearer 60mpg, but this number is affected more by the way you drive than having a bike on the roof.
I compared the parts list for the 815 with the parts list for the 835XTR Hull-a-Port that appears on Thule's website and they're almost identical. The only differences are that the carriage bolts and end caps, while the same size, have different part numbers, and the 815 does not include the two 1/4 inch Rope Ratchets that are included with the 835XTR. While the Rope Ratchets are nice for tightening and securing the bow and stern tie-downs, they're not really necessary if you can tie a decent knot.
"Was skeptical at first to see how good their prices were until I saw their Yelp reviews. Best prices out there for crossbars and racks hands down. Shipping was quick despite the fact that Rack Warehouse is located in the East coast (I'm from CA). The same positive feedback can be said on the care the items were packaged. For those unsure if this business legit, not only can I attest to the authenticity of this business but Google has their back too. BTW, Google provides complimentary insurance. Thanks Rack Warehouse I wish I knew about you sooner.
TYRE DEFLATION: This has never happened to me. In theory if this happened during transport then the bike would become considerably more loosely attached. I don’t think it would fall off as the two front arms are locked together in place. If you purposefully deflated the tyres before attaching the bike to the UpRide then I would guess that vibration during transport WOULD damage your wheel rims to a small degree. Thieves MAY deflate your tyres to make the bike OR WHEEL more easy to remove – remember they can easily take out your wheel skewers.
One caveat is the measurements in the instructions to install the bars are wrong, not really sure where they came up with those (or maybe there were for a different length bar? I went with 60" which seem perfect for my van) but after a little finagling was able to get them evenly set up on my own. Not even worth taking a star off in my opinion, but I can understand if someone were confused or unhappy. I'm mechanically inclined so it was maybe a 10 minute bump in the road, just had to figure out what measurement would be equal from the end of the bar to the edge of the foot on each side of the car, and beware, the front and rear bar measurements will not be the same. I started by eye and refined it by measurement, and put a sharpie marker on the bottom in case I have to remove them, done and done.
If you already own parts or just want a complete set of used roof bars, then use the roof bar guide to find your vehicle, then at the bottom of the page, if we have used equipment available. you will be able to order separate items. Do note even though you have some parts always double check that you have the right length of bars and foot pack. To do this just look at the relevent package options, we list the items in that package that you will require for that vehicle.
I am not sure if it would be possible to have 3 or 4 UpRide racks on one car. 2 is certainly possible. 3 probably is possible but I doubt if 4 would fit together as the UpRide is wider than the other Thule bike racks. The following image shows the UpRide as the third from the left – as you can see it takes up quite a bit more space (width) than the others. Then again, maybe your car is wider than my estate.