Sorry, I guess I should of mentioned that yes I am ordering from t-molding.com and have a few free smaples from them at the moment.
Ill probably be using their normal 'ol Black 5/8" or 3/4" with my 5/8 MDF.
I see their 5/8 lists a 3/32 spline, and the 3/4 says 1/16 spline, but I have both in front of me, and they look the same. I also recall hearing people use 1/16 bit for both 5/8 and 3/4, so do you think 1/16 bit will be good?