The intent of this thread is to expound beyond the issue list at the Tascam web site.
Here are specific bugs that limit my ability to utilize GS3:
1) The GS3 Orchestra crashes the XP Pro sp1 OS fatally when attempting to load instruments into memory over the 71% mark. To reproduce build a performance in GS2.5.4 that loads up to 99% memory. Save before getting any error message. On a machine with GS3 and access to the exact same gig files, load the performance. GS3 loads and plays it, reading 71% memory. Attempt to load another instrument. The XP OS crashes and burns. On a good day you get a cryptic warning message before the OS pops, but even then a second attempt to load an instrument kills the system (it is worse than blue screen, try it you'll see). Scenario is not good when in the midst of a session with a client. It is a bit like the Limo gas gauge reading more than 1/4 full when the tank is empty and the car is on the highway.
2) The 'New Performance' item off the File menu (and toolbar) does not work. Similarly, save an empty performance when the application is first launched. Now try and load it at a later time to clear out memory. Only way to clear all sample memory or build a new performance from scratch is to exit the application and restart GS3. Essentially the very first item off the file menu is broken, and memory management over all is in question.
3) Listed on assorted forums' threads: MIDI program with bank changes do not work smoothly. This is basic functionality that is unforgivable if broken on a hardware synth, sampler, or rompler. This broken feature gives the current GS3 software the vibe of being a public beta (I wrote this before seeing the other 'public beta' comments).
4) GS3 is not easy to install cleanly. Uninstall GS2.5.4 from a machine. Run gigaclean. Correct registry by hand for MIDI section to prevent super buggy overwrite (see the RME HDSP9652/9632 document from another thread, it applys also to .dll's for other sound cards and/or software that can be in the same slot). Now do a search of the registry for items like 'Nemesys', 'Tascam', 'Gigastudio', 'Gigaedit'. Decide for yourself if you are ready to install GS3 or first to manually delete remaining giga registry entries (attached to things like the shell) that Uninstall and Gigaclean missed. Even with a fresh install of the XP OS, that Midi section in the registry needs to be manually attended to (dependent on sound card).
5) Hold and sustain one or more notes. Double click an item in quick sound to load it (perhaps by accident, just looking for an instrument). Listen to something like a broken test of the emergency broadcast system for the duration of the load (can be a long time depending on the size of the instrument).
It only takes about 1/2 an hour to get a Tascam GS3 tech on the phone (cool, at least you can get one), but they don't necessarily put your bug or feedback into a database. Tascam support can not give you a case or bug number.
On a positive note, after a clean install and a 'tip toe' approach to the software, I am able to get 702-720 voices off a two drive SATA raid and top of the line P4. Gigapulse is cool, and puremode is only costing about an extra 4% on the CPU gauge (however if puremode is on, there are audible clicks in the audio stream even though no notes are being played. Occurs while GigaEdit is open and idling). The VSL content that comes with GS3 is outstanding and the VSL 16 bit versions work with GS2.5.4 (a consolation prize for attempting to get GS3 to work in a production capacity).
I enjoyed the demos and look forward to purchasing some of the new GS3 content when the application stabilizes, responding to program/bank changes correctly, and doesn't crash and burn the OS quite so easily.