I would like to know how many Pro XS and XS motors in service is having coil failure..

At 103 participants (9/11/09), the failure rate was computed via "reasonably acceptable scientific calculations". The Highest, and one of the lowest (zero) figures were removed to account for errors.

On the remaining 101 engines:

606 total coils. 88 Coils failed.

Estimated Failure Rate: 14.521% (15%), or approximately 1:6