Any known complaints about the VP-X Sport?

[waveflyer]

HAPPY NEW YEAR TO EVERYBODY ON THE FORUM
I fly an RV7A in the UK which is fitted with a VP-X Sport. It has performed without fault (except one incident which was entirely my fault) for well over three years. I regarded it as a great piece of kit.
Within the past few weeks and subject to inspection, Experimental aircraft (called Permit in UK) have been cleared for NIGHT/IFR. This has been as the result of a huge amount of work by a small group of owners.
There is resistance to aircraft fitted with the VP-X mainly due to the fact that details of the unit are a bit sketchy and the manufacturer, allegedly, will not divulge details of the testing that has been done. It is therefore regarded with suspicion by some and MIGHT not meet with approval for NIGHT/IFR use.
As an owner I may now have to prove if is a safe unit to get clearance.
Can the forum tell me of any known problems with the equipment or any persistent faults particularly if they have effected safety?