For all those who know what's going on, here is the question.
Why is it that some Skaters have #6's with the skegs cut off instead of using BPM drives, whereas I do not think I have ever seen an MTI with this set up? Is it so that they do not have to notch the transom for the BPM, or is this package more reliable, is it to have center of gravity farther back instead of having a large bussle? Both are for sure badazz but is there any advantage to using the #6? They don't turn in that application right?

I am not sure what notch you are talking about for a bpm? MTI's and Mystics are probably the two biggest users of them and they don't run notches.

The main advantage of a six is that they can accelerate/trim better/faster than a surface drive on some applications. They are fixed in position so they do not turn. You still need the bustle to mount the rudder in either case. The weight difference is probably a wash overall (sixes are heavy).

Here is a MTI with the sixes in the arrangement you are talking about...

sorry, maybe notch was not the right term, on the BPM boats, it looks like the bussle is much lower to the water due to the mounting point for trim on the top of the BPM drive. Are they pretty close in drive height/x dimension cause both are surface drives or surface piercing drives?