Freddy-
I've got the 3805 paired with Studio Reference 100's v3, the 570 v3, and the ADP surrounds (soon to be ADP-470 v3). The combo is awesome.
To shed light on an often confused issue...the Reference line are fiercely efficient speakers (91-93 dB if I remember correctly). However, the 100's have a huge impedance dip down in the low range (to crank those 3 8" woofers) that often demands some extra power. The other speakers in the line don't have this issue. They are efficient and easy to drive.
That being said, I bi-amp my 100's with the extra rear-surround amp channels of the 3805. The sound is fantastic and the 100's really sing with the extra power. If you're planning on a 7.1 setup and are considering the 100's, I'd definitely recommend a dedicated 2-channel amp for the front end. If you're going with 5.1 or fronts other than the 100's, you'll be fine with what the 3805 has to offer. I'll eventually add an amp, but it's not at the top of my list right now.
See if your dealer will let you do an in-home audition. That's really the best way to tell if you like the combo.
Jason