Don't be mislead by all the anti TANE comments you see here, those sort of things get said after every release !
If you think you are going to get a, somehow, vastly superior product in TS12 you are wrong - TS12 was a culmination of 10 years development and as such it's the most complete and rounded so far. TANE is a completely new game 'engine' and allows for much better visuals and other features, not all of which are implemented or used in the current SP1 HF2 version but the potential is there.
If I were you I'd stick with TANE and post questions about your problems on this forum so that you can get help with them.
Updating TANE if you are on an earlier build is quite straightforward and I think the whole thing will auto update now, so you don't need to do any more than click a few buttons.
HTH
Chris