The horn pictured is the horn that I once owned and the photos of it were taken by me!(probable they were downloaded from ebay) Who better to review this particular horn!
This Opus 7 had the sterling silver bell option and had a very nice tone with awesome projection. Overall intonation was good but the 4th line D was unusually flat. The resistance issue was the reason I got rid of it. A 2 hour concert was an excruciating experience. The 1st and 3rd slides never moved freely enough to allow them to be useful intonation aids and the 3rd slide ring was uncomfortable. Too bad such a fine sounding horn with an expensive bell option had so many problems.

My Opus 7 has a .458" bore with a brass bell (entire horn is silver plated). An interesting feature of this model is the concave finger buttons, presumably designed to position one's fingers in the center of the assembly, making them slightly more comfortable than flat ones. I purchased this cornet because of the beautiful sound it produces. At first intonation was problematic; it was inconsistent throughout all registers, and I also had to pull the tuning slide out twice as far as any other horn I have ever played in order to be close to being in tune. I considered selling the horn until I tried Mark Curry's DC series cornet mouthpiece; it resolved the intonation problems to a decent degree and in addition enabled an easier upper register while making the already beautiful sound even better! With this mouthpiece endurance is not a problem, and it is not "stuffy", either.

All slides required fitting to work properly; it would have been nice if the factory had taken on this responsibility, but they didn't. Also, the slide ring and saddle on the third and first valve slides, respectively, were awkward and unsuitable for my hands. The pinky finger hook on the leadpipe was in the usual King position: too far from the valve block. Also, the valve springs are weak by design, unfortunately, and the valves, which were tight, take a long time to wear in. The other side of this coin is that I expect that they will never wear out! Anyway, I either corrected or had corrected all the mechanical and ergonomic issues, and now the horn is a pleasure to play and hear.

If you are willing to deal with the initial shortcomings of this cornet by getting the mechanical issues adjusted and find the right mouthpiece (The Curry DC is magic in my opinion, an opinion that is shared by others), you will have an instrument you can enjoy the rest of your life.

I wanted a short (shepherd's crook) cornet and went to look for a nice one. When this one came up, i read the reviews here first. The reviews here were not great, but I'm glad I took the chance to buy this little cornet anyway.

It has a nice warm sound and can be loud when pushed. It' is at it's best when used with a heavy mouthpiece. I use a Denis Wick heavy top. I'm surprised about the "stuffyness" I keep reading, as I don't have that problem at all.

The valves are quick and flawless, as with all Kings. To me it is a great catch.

By the way, these were not made by UMI, imho, but were produced during the KMI period. They were the top of the line for King during that era.