Truespace 3 isn't bad at all. it lacks bones, but does have IK. (although rather lame) TS3 was the first TS version to have a plugin support, and you can still get many great free and cheap ts3 compatible plugins. (I highly reccomend Thermoclay, or really anything by Alain Bellon.) I still use TS 4.3 and as a modeller TS 3 is just about as good.