Help with existing audio equipment for new HT

[AVRat]

If you're talking the E5Bis for surrounds, then yes they would work just fine. It's not as critical for the surrounds to match the timbre of the fronts.

For the sub, I'd still do something else as the 10i only digs down to 35 Hz.

 

[AVRat]

For the center, 3 that come to mind are:

Ascend Acoustics CMT-340C
Def Tech ProCenter 2000
Polk CSi A4