I've just purchased the IXEG 737. Deeply impressed with it in so many respects despite some missing functionality in the FMC especially.
I use a VRInsight FMCU and, thanks to the wonders of Linda and its custom modules, have it set up beautifully to operate my entire fleet of aircraft in both FSX and P3D.
X-Plane is relatively new to me but I can see myself using it more and more now that the IXEG 737 is available.
I'd really like to configure the VRInsight to operate all the main controls - barometer, VOR switches, lights etc - though at present (using the basic VRInsight software) I can only operate speed, heading, altimeter and Vertical speed.
If anybody out there is in a similar boat and/or has any bright ideas then I'd be very happy to hear from them!