We use these in our church, both this 'single-ear' and the 'both ears' mounting types. I can't imagine the Sennheiser original version would be any practical improvement on the sound, feedback rejection, ruggedness etc. Perfect match with the Sennheiser belt-pack.
It comes with a small foam pop-shield to go on the tiny mic, but we find it's not necessary for indoor use; just don't bend the boom-arm; the mic it so sensitive, it doesn't need to come around and point straight at your mouth. We get great clarity both for the live PA signal and for the recordings of the sermons.
When I wear this model I find it's more stable on one of my ears than the other! but I guess that's a review of my head, not this product. Inevitably this isn't as stable on the user's head as the version that hooks onto 2 ears. If I complicate matters by also playing a guitar, that just adds one more way this headset could be pulled off my ear, so I go for the 2-ear version.
We find people with long hair like this version because there is nothing going around the back of the neck.