Do you currently have 20" wheels? If so, when you purchase your wheels, for simplicity reasons it may be best to stick with the current OEM backspace/offset, as that will also play a major role in tire fitament. Tire size + lift height + rim size + backspacing/offset = a headache for me, as I am not mathematically inclined enough to figure out what will rub and what won't when all of those items need to be factored in. However, there are many on this forum who can figure out this crazy equation (I think they all have a Master's Degree in Engineering), and maybe one of them will be able to provide you more prescriptive advice soon....for now, it's just me!
It appears that the 295s are about 1/2" taller and 1/2" wider than the 285s...and both come in under the 33" diameter height. If you have the 2.25" readylift kit, I think you should be fine. However, if you really want to be on the safe side, ask the tire shop if they have a tire that size running around that they could mount up for you. I had this done at a tire shop when I was shopping around for tires and they did it for free as they wanted to make sure I had the right/best size. But even if it costs you $20 it may be worth it. I would have gladly paid it as the tire size I originally wanted was not the one I ended up getting. I was able to go another size up, which really made me happy! And again, if you new wheels have the same backspace/offset as your stock wheels, then it will be easy to know whether or not your new set up will fit.
Yes, the TPMS will work with the right stems and do not need any other connection (this is how they can work when you rotate your tires); however, I have never purchased them before but $200 sounds like a lot of money for those. Maybe they can use the ones from your stock rims?? I'm not sure but it may be worth asking.
I pasted a couple of links below that may be of help to you.
http://www.1010tires.com/TireSizeCalculator.asp?action=submit
http://www.rimsntires.com/specs.jsp
It appears that the 295s are about 1/2" taller and 1/2" wider than the 285s...and both come in under the 33" diameter height. If you have the 2.25" readylift kit, I think you should be fine. However, if you really want to be on the safe side, ask the tire shop if they have a tire that size running around that they could mount up for you. I had this done at a tire shop when I was shopping around for tires and they did it for free as they wanted to make sure I had the right/best size. But even if it costs you $20 it may be worth it. I would have gladly paid it as the tire size I originally wanted was not the one I ended up getting. I was able to go another size up, which really made me happy! And again, if you new wheels have the same backspace/offset as your stock wheels, then it will be easy to know whether or not your new set up will fit.
Yes, the TPMS will work with the right stems and do not need any other connection (this is how they can work when you rotate your tires); however, I have never purchased them before but $200 sounds like a lot of money for those. Maybe they can use the ones from your stock rims?? I'm not sure but it may be worth asking.
I pasted a couple of links below that may be of help to you.
http://www.1010tires.com/TireSizeCalculator.asp?action=submit
http://www.rimsntires.com/specs.jsp