Adding; I think there is a great deal of misunderstanding about the MSing laws in NV, even by registered shoppers and MSCs. I would suggest that anyone who has concerns about it take the time to read the law carefully, and not to exclusively trust advice from MSC's, the PILB staff or anything read on the internet...including here.
It's not that there are 5 MSC's which are licensed to do business in NV. All shops must be performed by shoppers that are employees of a firm that has a NV PI license and is overseeing the shops. Five MSCs employ PI's in Nevada, but there are more than 5 PI firms there, and MSC's have the ability to utilize other firms as I understand it.
In the past, I was employed by PI firms that operated outside of NV and the law was somewhat recently redefined to include only NV based firms. That made shopping in NV less interesting and less profitable for me, and I elected to let my license expire.