Hi - I have heard that the rear parking sensors need to be deactivated as they register the rear tire as an obstacle. Is that correct? Also are you able to use your rear view camera or is the view significantly obstructed?
I will let Kevin (ExPat93) answer those, but based on my questions to him and quite a few people (including Ben at Outback Proven), the spare tire does trip the parking sensors; however, I think Kaymar has a reflector that is supposed to help, though I have heard that it still does not always work. I think the camera is only obstructed if you go with the LHS swing-away, or even the dual swing-aways.
Personally, I also like the fitment of the Tactical 4x4 bumper a lot better, especially the bar steps on the ends. From what I have seen, it fits very nicely on the LR3. There is no official rear bumper for the LR4, but Eric offered to fit the LR3 bumper to my LR4 when they are not busy. He was going to let me know, as he has been wanting to have a template. If you are interested, I could let him know and we can go down to S. CA together. I am still doing research, but leaning toward the Tactical 4x4. I don't like the gap on the Kaymar and do not really like the idea of rear mud flaps, though I like the look of the Kaymar in many ways.
I actually put my spare on the roof and it helps cut down the wind noise on my roof rack - haha! If I go with a swing-away, it will be a right hand side and do NOT want it to block the rear tail lamp or camera. If I have to disable the parking sensors with my IIDTool, then not a huge deal, but I prefer to keep them active.
Pedram in the NCLR is building Don a custom rear bumper, you can see those pics (though they haven't posted anything recent) on the NCLR forum. If I go with a swing-away, I will have Pedram make it.
I know you don't like the front ARB bumper, but we are installing that with my winch on Saturday.