With regards to anemone guards I've not seen any but to be honest I've also not looked. I've used various manufacture Gyres with Maxspect being the most powerful out of the lot without issues. It really comes down to placement and if the anemone decides to roam.
If they roam it may be due to display conditions that it doesn't like or make it feel secure. Anemone type makes this somewhat different for each. I have rose bubble tip anemones and they like to take hold deep into rock crevices or along the display glass but surrounded by lots of rock.
In short I have not experienced any anemones of mine getting pulled in by the Gyres. Mount them properly, the Gyres, and this shouldn't be an issue.
You mentioned keeping a SPS dominated display. I would recommend a hard pass. I say this as a hobbyist keeping a mixed reef with several large SPS colonies. By large I mean 20 to 26" in width. Depending on the anemone type one can become two. Two become three. Three become six, seven, and before you know it you have twenty or more taking up space that you may want for the SPS corals.
If one starts to walk because it is getting too much flow it may walk over a SPS colony. If it moves to a new spot again for any reason unbeknownst to us it may sting the SPS coral and damage it. Healthy anemones may spawn. It happens to me a couple times a year. One going off isn't too bad. Two or more going off at the same time and my display looks like a storm blew through mixed up the sand bed it is so cloudy white. Skimmer is going nuts and a water change is in order.
Focusing on a single type of display such as SPS I would say no. This is, of course, my experience and others may have different ones.
Welcome. Hope your day is well.