Thanks for the correction Brian.
The T54E1 reloads in 30 something seconds.
The T57 reloads in 22 seconds
I think I'm likely going to sell the E1 because of this; it is just more fun to play the T57.
With the E1 I've been using its lower Tier gun which is 5 shots instead of 4 and 22 second reload instead of 33 - just to screw with people who assume I have 4 shots