backert vs sachs preamp

I've been using a passive preamp and was initially floored by its detail, but the novelty has worn off.  I've read every post on the active passive debate and agree with atmasphere's comment that the passive is actually coloring the sound.  So I'm going back to active - looking for the best of both worlds - transparency and dynamics. Based on my reading and conversations I have narrowed it down to 2 to audition, a backert or don sachs.  The backert I can audition but the sachs I may have to purchase and resell if I don't want it.  Does anyone have any experience with both of these preamps? I will be using it with quicksilver M60s. Thanks.  
Don Sachs preamp is a giant killer.  Their cost relative to their performance is tremendous.  Backer has modded equipment for me and he does good work.  Sachs preamp is for sure cheaper with out of this world performance.