Congrats on the purchase. My 635 was my first experience with MF; got it back in April.
Just a heads up -- there's a little knob on the left side that has something to do with the 35mm loading side. All it does on mine is make a dark shadow on my negatives, even when I remember to pull it out and rotate it (there's a little tooth in it that's supposed to line up). I can't figure out if I'm just doing it wrong, but I always forget to check, or bump it (it's spring loaded, so it'll go back to the Mess-Up-Negatives position).
Not sure if there's anything that can be done about it. Mine always gets in the way -- I might look into filing it back a bit or something...