In my experience as a full-time shopper since late 2008, I have seen no difference in the number of shops I can see. I think location, merit, diversity, experience, demographic fit, .quality of work reputation, and availability will determine how many shops you see and get assigned.
Geography is everything! There are thousands of assignments hundreds of miles from me. I never have been to many of those places and am not out of rotation there! Clever shoppers from here go as far as they have time to go and make more money than I do in this biz. Mind you, I would not go too far to chase them. I like where I live, even though the wind farms have utterly disrupted the sense of space and spaciousness that contributed to my ease and relaxation, thereby providing well-being. They might as well be skyscrapers, or Goliaths, or something, in that they give the impression of being infinitely more important than the few glimpses of what remains of a simple landscape that stretched for miles and miles and miles..... Just now, I am out of rotation and have no time for the local assignments. Eventually, I can put together a few shop/merch days.
I had a silver certificate years ago. I did not renew it or go for the gold. I suppose that a good and helpful alternative to that type of certificate is to read the information that each MSC provides for us and take as many qualifying tests for as many shop types as we want to try. As you delve into more and more websites, you will note that some MSC's offer more qualifying opportunities than others do.
Rest is not idleness, and to lie sometimes on the grass under the trees on a summer's day, listening to the murmur of water, or watching the clouds float across the blue sky, is by no means waste of time. - John Lubbock, "Recreation," The Use of Life, 1894
I’ve noticed that everyone who is for abortion has already been born. - Ronald Reagan