I bought one of these thirteen years ago. One of the best things i ever bought for making life easier as you get older and start noticing it.
The one i got is identical in size to the 800 lb one you are looking at. I find it plenty big enough for my 600 Fazer but i guess an advantage of the bigger one is there's more room on the table for all the tools and bits and pieces that end up on it from the bike. In my case I wouldn't want anything bigger because I've not much room to spare in the garage, but if space isn't a problem then the 1000 one might be a better bet for the extra cost. There are some about that aren't even the length of a motorbike unless you include the ramp, which I would certainly avoid. Not surprisingly you see them for sale secondhand!
I've never found a need to remove the lift out section at the back to remove the rear wheel. On mine (like the 800) it could do with a longer ramp so it's not so steep when pushing the bike up. Be aware the whole thing has a tendency to slide forward when the front wheel starts to go up the ramp, even with the front two jack things screwed down. I lost balance and nearly dropped the bike when this unexpectedly happened. I always chock mine at the front with a length of timber to the base of a solidly mounted lathe in front.
As already stated they are a heavy piece of kit and not a one man job to get in a van or on a trailer.
Definitely brinks a new joy to messing with the bike.