I bought the Shure e5C -
I still have the ety ER4P.
I use a Xin mini amp with bass boost and both sound great once you get the external ear canal fit right. I found the larger foam ear buds that are made for the ety's to work best in terms of bass response. I also had custom silicone ear plugs made by an audiologist but found them too finicky to insert and somewhat uncomfortable unless positioned perfectly. The foam expands to conform to the shape of any ear and seems to get as good sound isolation.
The noise generated by the ety cord is annoying and the fact that they stick out of the ear canal makes sleeping on the side difficult for plane rides. I read a post somewhere which describes a way to get the ety cord over the auricle and use of a rubber strap similar to the Shure configuration to get rid of the cord problem?? Has anyone heard of this??
As far as sound quality, the etys have the best top end detail and clarity but at times can sound overbrite and etched(for lack of a better word). The bass is clean and well controlled with no boomy quality but still is weak compared to the Sures or over ear head phones.
In a direct head-to-head comparison (IMO), for general portable listening, the Shure e5C are fantastic but sound muffled and at times boomy compared to the Etys. However, the richness of the midband can't compare and I think is a more real to the source rendition. I will keep both and use them interchangably.
I also have a pair of Grado 80s and think thse are fantastic and combine the best featrures of both of the above canal phones. For home listening and in outdoor quiet places, nothing is better for the money!!!