I am currently using a B&K pre. set for direct bypass. Would I find much of a difference using attenuators?
From my experience you will probably hear an improvement, depending on the attenuators of course (EVS?). Source selection may become a bit more difficult.
I have no idea what attenuators I would use. The last 2 systems I saw setup this way. Doesn't look like big dollar change to make. A good SACD might sound even better?
Sorry, but I don't understand your SACD question.
EVS attenuators will absolutely kill your pre amp sonically.
If you're a purist, you owe it to yourself to hear attenuators directly connected to your amp. Separate attenuating components i.e. Creek, Mod Squad etc. are less good. They require an extra set of interconnects, which is most definetly not desired for the cleanest signal transfer.

The attenuators would make bad recordings sounds worse and good recoedings sound better. I am using a DVP9000,Athem amp2,and Totem forest speakers.
I might consider selling the B&K in favor of a Placette or an FTAudio(no remote) passive preamp if your setup will work with a passive pre. I know you can try the Placette for 30 days risk-free(and maybe the FTAudio too), so it might be worth a try to see what kind of improvements you get. These units fall between active preamps and attenuators in terms of transparency, so I guess I'd think of them as a convenient compromise. My guess is the improvements will be substantial assuming your source puts out at least 2 volts and your amp isn't a bear to drive. Best of luck.

What about Virual mode dual mono? What kind of unit is this? A local shop has one for $170.00.