the original TM9100 is shite, i had 4 of them, and got rid of the lot, but the TM9100Super (aka TM9101) is a much better machine
the first 9100 (IMO) was rushed out before it was ready, and not tested enough, which meant that as soon as it was widely available, all its problems arose, and only about 4 monthas after, it was replaced by the super version, not before a certain un-named site had a 'special offer' on them though
TM learned from this mistake, and held off the release of the TM500/600 untill they had tested it to death, and theyre now (again, IMO) one of the most stable linux receivers in production
the TM800HD has been delayed quite a few times, but if once its released, its only half as stable as my TM600, itll still be better than my original DM800
Id say to buy the TM600 instead m8, i own a TM500, 600, 9100super and have had 4x 9100's, as well as most dreambox models