I have both pictus catfish and bristlenosed plecos. No problems with any of these fish not getting along with anyone else in our tank. Actually, when the bristlenose comes around, the pictus cats leave!
The place I got my pictus cats said they grow 8-10 inches. I was recently at a pet store on the other side of town here, and saw two pictus catfish in a tank. These things were HUGE. I even asked to make sure that's what they were. So these guys were about 12-14 inches, and, quite big around too.
Angie