Well, Action is vastly superior to the specialists, however the bots for TS are much better, so I'll play that.
If anyone wants to arrange a game however, I prefer AHL.
The weapons are better, the stunts more fun, the maps are better. (From a gameplay perspective, I liked bikini) I must say a lot of them felt like AQ2 rejects!
The handcannon really bites in TS.
[EDIT] Just to clarify, the models are better, as well as the modelling of the weapons.