I was recently lent a RA0SMS mini-whip to try out. Earlier this year I purchased new original Mini-whip from PA0RDT. I have used a homebrew copy of the mini-whip I built a few years ago as well. The new one uses an isolation transformer in the receiver interface as does the RA0SMS antenna. I installed each one in succession near where my CliftonLabs whip antenna is, about 5 feet off the ground strung from a plant hanger 80 feet from the house and more from the road. I have a wideband rf choke designed by CliftonLabs on the feedline about 3 feet from the antenna.
The RA0SMS antenna seems to have a lot more gain than the PA0RDT antenna. It really brings up the noise, anything above 20 MHz is unusable in my installation. As I have mentioned previously the noise floor of my KiwiSDR rises above 20 anyway. They both receive well, especially considering their size and ease of installation. Both receive WWVB with the RA0SMS doing a bit better.
I have attached a spectrum image of each antenna, the capture were about 10 minutes apart in the morning here in upstate New York.