The Mason Tech plates do a different job, as has been said...and again, are a sound idea.
However, once again, you are transferring the load from the rear beam into a 10mm plate and some very short bolts.
Yes, it lengthens the wheelbase back to where it should be on a standard height car, so takes the wheels away from the point where the tyres usually catch the arches...but to me, it's adding a failure point.
I'd not use them either....although, they are less likely to cause 'issues' than drop plates in my mind.