I will throw in my 2 cents here owning a 10" spacing SeedMaster, a 9" Bourgault PHD with 2" spread tips and MidRow banders, and currently a SeedHawk twin wing on 12" centers.
SM - I only harrow once, unit would not clear trash on 10" spacing. Huge problem where I'm located. 12" spacing may be better fit, but only single narrow openers from SM as far as I'm aware.
BPHD - Best field finish of all drills I've owned. Best trash clearance of anything I've owned. Switched to twin wing because I didn't like maintenance of MRB, and didn't like having to put majority of my fertilizer through MRB which was farthest possible position from seed. (unless you put in someone else's field).
SH - Twin wing is best drill / opener combination I've owned for seed and fertilizer placement to date. Best germination for canola by a fair bit. Field is rough due to deep trenches though. Trash clearance is very good. I currently am not running the SeedHawk tank because when I demoed couldn't load from superbee without having 2 guys in field. (maybe new one has changed). Running BG tank, which I believe is the easiest and most flexible tank on the market.
I pull a 70' SH with 950 BG tank with 530hp. It is not over powered by any stretch, but gets the job done maintaining 5mph most of the time except on steep hills, and bog.