If you can deal with the extra noise and extra electricity cost, I would go with the T9.
The sick R4 is in a DC with my S9 so noise isn't an issue in this case. Just another expensive shipping payment and then mining delay, what fun!!
Well after much delay my sick droid R4B4 is back at the Empire for scrapping. After some polite back and forth regarding the issues with the R4 I was promised "just this one time" an S9, instead of a T9, for swap once returned on my dime. It (R4B4) has just arrived today.