I've not heard anything bad about the tiny terror, and even if something does happen oranges after sales have been pretty good to me in the past. The most recent 500 is plenty loud enough, I A/B'd one against my AD200 through my 8x10 and there wasn't a lot of difference, The terror wasn't as warm but id did have a more precise sound. having said that I think I'd go for the 1000w for the price difference.
If you want light weight cabs the SP ones are great, I think you can still get the 4x10 too? failing that cabs are up to you really, Speaker configs are quite a personal thing in my opinion.
I hope that helps.