Despite the strong favour in the larger aperture scope (which you will get every time you ask this sort of question), I would recommend you spend a bit of time observing with both before buying if you can, and assess how comfortable it is to use both scopes and how much difference there is in what you can see through them.
Don't get too hung up on the numbers. (Let me explain why with more numbers.
) The 44% brightness difference is noticeable but rather marginal (many newbies cannot tell the difference). The eye has a dynamic range spanning conservatively a 100000-fold increase in brightness, so a 44% or 1.44-fold increase is not huge by any means.
And consider that the 10" will probably get more use; maybe over 44% more!
