It depends what tips you are using. If you are using foam tips it should be the same.
The Ety tri-flanges also have extreme isolation but I don't know anyone that would use that tip on a Shure product. More likely a single silicone type tip which would provide less isolation. I would gauge 20-25% less isolation.
i use the triple flange for it .... after cutting the upper small tip ( so it is double flange now )....it is great and i am using it for now ..... less isolation from the foam one by about 20 -25 %