Thomas Horn, Jr. November 21, 1860 November 20, 1903 was an American Old West scout, who carried out varied roles as hired gunman, Pinkerton, range detective. Back to myself, as I write this I am doing a more extended trial of the Kelly MC. One suggestion I originally received was that the plating could be starting to go on my normal gold rim so I switched to a freshly plated example but that did not do the trick. My lips really seem happier on the plastic rim, particularly the clear Lexan Kelly MC. I have a titanium coated rim on order and will follow up more on that after I have a chance for a fair trial period. I suspect that I may end up playing the Kelly mouthpiece on my triple see the UPDATE part of the review for more on that and a H Kote or Delrin rim on my normal mouthpiece on the double horn. What about horns I think perhaps better known in the horn community is that some players have nickel allergies and are allergic to nickel silver horns or parts on horns. Lacquer and hand guards can help greatly, but in the longer term you are best off playing a nickel free brass horn. Several makers offer custom horns that are completely nickel free. If you know you have sensitivity to nickel, probably you would be wise to think about moving to at the least a gold rim and perhaps more exotic materials before you notice larger issues in your playing. At least keep a few options around such as a plastic mouthpiece. For more info This article just scratches the surface of this topic and there is much more out there. The Wikipedia article for example has good, general info on Allergic Contact Dermatitis. A quote The symptoms of allergic contact may persist for as long as one month before resolving completely. Once an individual has developed a skin reaction to a certain substance it is most likely that they will have it for the rest of their life, and the symptoms will reappear when in contact with the allergen. Once an individual is sensitized to an allergen, future contacts with the allergen can trigger a reaction, commonly known as a memory response, in the original site of sensitization. To close, this is a serious topic that is certainly not much reported or understood in the horn and brass playing community. I believe that many readers may have borderline metal contact allergies it is a topic very much worth exploring further. UPDATE I have settled in to use a Moosewood Delrin rim on mostly Moosewood cups. I wish it was a little slicker feeling, but then again it feels great to not worry about metal allergies when I am playing on the plastic rim. UPDATE II 2. 01. I have moved on to a different Delrin rim, the Osmun replica rim for the Conn 5. BN. I like the feel of the black material they use better, and the shape suits me better as well. Currently using it on a Houghton H 2 cup.