81 cleans are pants. 85 cleans are tolerable in the bridge, Ok in the neck. The 60 in the neck is my all time favourite clean and 81 bridge my go-to high gain sound these days. I still have BKs, and enjoy certain things about them rather a lot, but for my bread and butter metal rhythm sound, I like the 81 for various reasons that I shant bother going into any further.
As far as blackouts go...this was done with ABH1 7 strings, in A in an RGD somethingorother (it was a 'prestige' model). Its worth noting that blackouts arent as tight or clear as 81s, and are a LOT hotter and fair bit mushier; I A/Bd the guitar this was recorded with against my 81 equiped guitars, and even though mine are normally in drop B and strung 12-56 on 25.5, and this guitar was drop A, 12-64, 26.5", detuning the 81s to drop A still yielded a tighter sound. Some parts of the clip are faster, played by a massive fear factory fan, and may be of interest to you.
http://soundcloud.com/mdv/rooted-seek-solace-in-ruinMeanwhile this is an 81 through a similar setup. Different treatment and tonal objectives for the tracks render direct comparison a little problematic, but much of the difference between the tones is the difference between the guitars; it was the same amp and cab, quite similar micing.
http://www.youtube.com/watch?v=L5b0XUmzah0