Most of the time, we have used the most expensive solution, like the one from Keysight. Then, Anritsu came out a bit later with their solutions, but for a cheaper price, which is why we switched.

So far, this is the only tool that I have used for S-parameters. If I were to switch it would be because the bandwidth of the next VNA is wider.

We received feedback from our team members (user experience), then we made a product decision.