Depends on how much space do you want to work with.
T8 is 48x24x12 while T10 is 48x24x15
The one thing to keep in mind is the interior dimensions are slightly shorter, by about 2 inches.
For example a T8's interior is 10 inches tall instead of 12 and the doors are 8 if I recall correctly.
T10 is a bit taller and will offer you a bit more space for ease of cleaning and access, as well as some vertical advantage for handling, which is one of the reasons I've personally went with a T12. Plus a bit of climbing space. It all comes down to personal preference.