Goyangi...

I received my buffers today. Initial impression is (as psyprof1 stated earlier) more presence to the sound. The sound is more forward. The 990 for me is more than satisfying for HT...for the synergy between the outlaws and my Mirage OM-5 speakers (laid back in the lower midrange) there was quite not enough musicality. These tube buffers/processors are a good enhancement. If you find this to be the case with your Vandersteins (which I haven't listened to since I was a teenager in the mid-80's) the buffers are a low budget way for more musicality.

To make my long opinion short...I highly doubt you will regret a 990 purchase. And you should be able to tweak to your satisfaction.