Thanks for the heads up. I bought an Ample Bass (AMR) just for the riffer.
One thing I really like about the Ample Bass is that you can send MIDI out. That means you can play the riffs with any bass instrument you happen to have on hand by placing it on another track, and setting the MIDI input as the output from the Ample bass. Set up your riffer, and off you go!
One thing I have noticed, is that Ample sends the MIDI data over channels 1-4, or 1-5, depending on whether you have 4 or 5 string bass. One channel per string.
For any instrument that you can set up as Omni input, all your strings will play. But with SampleTank 3, I had to create a multi with an instrument for each channel 1-5. Apparently ST3 does not let you select Omni for an individual channel slot like Kontakt will.
I really do like some of the bass samples in ST3, especially the Rickenbacker 4001, the P-Bass, and the Vinatge Jazz Upright. The fingered samples are nice to have, as my Ample Bass only came with picked samples.