Can I use a different ECU on my Civic Si??

What is your question?

I'm currently using a chipped Po7 ecu on my civic with a b16a motor it's been running good for the past 4months but it's starts to idle up and down and shut off only when I'm at a stop. Not sure if it's the ECU but can I use a different ECU on my car and have no problems or do I need the stock p28 for more long lasting reliablility I feel like it's the ECU or sensor not sure becuase every thing from the motor sounds good and no overheats or strange noises,please help!!??? Also it only happens sometimes and not all times I have some days that I don't have no issues mostly when I drive for over 40 mins. It starts to idle issue

What makes this problem better or worse?

Worse when I'm driving for a long time

How long has your 1999 Honda Civic had this problem?

For a few weeks