I have one of those, originally got it for an airsoft gun it was a Christmas present. It has been moved to mp15-22 rifle. It has functioned great in that role for several years. Had it for over a decade. As stated above many companies have copied the design but I believe the panorama is the original. Mine has been good. Wouldn't put it on a hard use gun but it's a great .22 red dot.
If you can find a Bushnell trs 25 it is superior in my mind.