while I'm getting to like cats(boats that is, the animals have owned me for years
)... I'm not too keen on the bj's outdrive setup, those u-joints just don't cut it. I would say that if you want to race then the sv is the way to go...(for the moment). one should keep in mind that when talking about 30+mph boats there are few that can handle waves over say 2".
your batteries might be up to the task...for either boat they'll need to be able to handle a 45amp draw(continuous) and, have deans plugs installed. intercell connections should be battery bars, not the thin welded tabs. the sv27 does have some issues that need to be addressed before running(imo), since I haven't been keeping up on the bj I don't know if it has issues, however the forum over at offshoreelctrics has a section set aside for both boats(one for each). hth and welcome to the world of FE boats.