In my opinion no, hopefully Darryl will be able to give you some further advice on this also.
But here is my understanding of it...
Firstly buffalo should not be mowed too low. It's bad for the health of the grass, increases the thatch build up (amazingly quickly in summer), reduces it's disease resistance and if mowed really low for some time can actually kill it. Buffalo should be maintained somewhere between 30-40mm in the summer months. In contrast couch will happily thrive at heights down to 10mm in summer.
The second consideration is the difference in frequency of cut between the 6 blade and 10 blade reel. Decreasing the frequency of cut (more blades or rpm) at height, can cause a fanning or turbulence effect that prevents the grass from being cut cleanly.
I'm not suggesting that you will have a worse or better cut with the 10 blade reel, though I don't think you will see a noticeable improvement with it on Buffalo. A 6 blade reel on a Rover/Scott Bonnar does a beautiful job if well setup and maintained. I have both 6 blade and 10 blade Rovers myself.
If you're interested to read some more to get a better understanding (and have it explained much better than I can), here are a few pages with good info...
Info on Cylinder Mowers and Frequency of Cut Dangers in mowing Buffalo too short Cylinder lawn mower heights for Buffalo grass 
