I've got one of these. Bought it new way back in the day. way back. I think it's a great preamp. Two different channels. One sounds very warm and tubey to me and the other is a more hi/fi sound. I like to use chanell one with an active bass, with the chanell one boost switch turned on and the pre volume at around 3.5. I get what sounds to me like a warm tubey sound with just a little bit of smooth overdrive. I don't have the BS mod on mine. There's a bazillion inputs and outputs on the back of this thing as well. Do a search here in this section and you'll find several posts about these amps.
Having said alll that, the one in that add seems way overpriced. I think I've seem them go for 4 to 4.5 bills and that still seems expensive to me. But hey something is only worth what someone is willing to pay for it right.