You should really check out the IK Multimedia group buy at Esoundz. For $49, you could get Omnisynth 2 (a GM module that works well in BIAB) and the acoustic guitar Xpansiontank. Since it's a group buy, you can also choose 2 other Xpansiontank title (such as the pianos or basses). If the group buy hits 2500, you can choose another title. The sounds play through the included Sampletank XT, which is a full version, minus the L or XL sounds.

I have Omnisynth 2 and it alone is much better than TTS-1/Hypercanvas. The acoustic guitar set is pretty good too, IMO.

Of course, RTs are still my preferred sound...