Received this from JR Porduct Support:

Bill,

Thank you for your recent email. Unfortunately we do not do any cross-brand testing of our products with other manufacturers products. So we can not verify whether our servo would operate properly when used in conjunction with another manufacturers receiver. I apologize that I could not be of more assistance.

I hope you find this information useful. If you have any further questions, please reply to this email or give us a call at 877-504-0233.

Thanks,
Tobias
Product Support Team Member
Horizon Hobby Distributors
4105 Fieldstone Rd.
Champaign, IL 61822
877-504-0233
[email protected]

Well, at least they answered. Not sure how to feel about the fact that they don't cross brand check anything. On the one hand, it would be almost impossible to check every combination of different brand receivers and servos. On the other hand this problem has been around for a while and you'd never know it without Forums like this. I guess from now on if I mix any equipment I'll have to search high and low on the RC Forums for issues like this. Clearly it is not as simple as just PCM technology being OEM proprietary.

Bill Gavin