Ken, the best way to answer this question is to test it. I did exactly that and ended up with the brush in-line with the blade. I tested one brush vs two, side vs head on, static vs ball bearing supported and wound up with a ball bearing supported wheel in line with the blade under the lower blade guide. I use a 1" fine wire wheel and it has lasted over 10 years at this point and has not worn significantly or needed replacement.
There is not a lot of definitive information on bandsaw brushes on the net. Lots of opinions but rather than rely on that, I tested it myself. I use only stick wax on my saw so I do not know how using oil or coolant would affect performance, nor do I intend to find out because I find the wax sufficient for my needs. What is most important to me is that my blades last a long time; my current Lenox Die-master 2 blade is going on to its 6th year and is still going strong and I believe much of that has to do with the chip brush.
As to how well it works, this crappy picture is Delrin. Sorry for the quality but that blade is running. Note that the right side above the Delrin bar is nearly clear of any debris.
View attachment 338075
That is what the chip brush does. So,
in my opinion, a single rotating in-line brush works well and seems to significantly extend the life of the blade. It is cheap and simple to make and has a very good service life. I have a write up on this that I intended to post but haven't gotten around to it.
Anyway, hope this helps.