yeah the lift up doors are so much more practical than the slide doors. The ARB canopies are a bit more expensive but having thoroughly compared TJM, ARB, Flexiglass and others I do believe that the ARB are well worth the extra money. Most of the canopies are fibreglass whereas the ARB ones are injected mould plastic, have better handles/locks and they also come with internal light (which is pretty bright) & high mounted brake light. The compatibility with the steel roof rack was also a big winner for me because I definately wanted that rack for it's strength and versatility (being able to carry long ladders, electrical conduit, camping gear, and being able to mount my mountain bike racks were all necessary)
I am pretty sure the rooftop tent will fit on the canopy roof rack, check the measurements with ARB, but the rack I have is 1350mm x 1800mm. I can't remember the rated loading of the roof rack, but it has really hefty steel vertical supports which penetrate through the canopy roof and fix to a steel rail which sits the full length of either side of the tub rim, so the weight of the roof rack and it's cargo is evenly distributed around the whole tub. I would be confident of having a fair bit of weight up there, if you add up the weight of a tent, bedding, plus two people, you're probably looking at around 200kg or so. I would be quite confident of putting that much weight (and some) on the ARB steel rack, but probably not so confident of putting it on aluminium roof bars.
