New computer advice needed!

[ATJ]

2) using 2 AI computers one on my wrist another on my camera strobe arm, although I don't know if the transmitters can interfere

Both Oceanic and Shearwater use PPE transmitters so you will only need the one transmitter on your regs. With only one transmitter there can be no interference at all.

The dive computers themselves are receivers and don't transmit anything so there will be no interference from them.

I have my computers mounted on my camera rig and actually have far fewer dropouts from my transmitters than I ever had when the computer was mounted on my wrist. My camera is almost always right in front of me (even when not taking photographs) so I effectively have a heads up display.