I had owned a real Silver Jubilee from 1987 for almost 20 years and had some sort of love-hate relationship with it. Mostly, because it sounded much too scratchy and sharp to me, the clean channel also disappointed me, it was clear that it would not sound like a Fender or Vox, but it also did not sound like a clean Plexi, unfortunately.
The crunch and lead tones sounded ok, if you looked for knife-sharp Metal tones at this time, but this amp was not the best choice, if you looked for typical AC/DC or ZZ Top tones.
The fact, that Slash started to use alnico II pickups with his Silver Jubilee, says all. They can compensate some of the treble overload and also the - in my opinion - more intense mid scoop, which the Silver Jubilee also offers, if compared eg. to a 1959.
Really good it only started to sound at very high Master Volume levels, which means, on a big stage. (Despite of even separate Input Gain, Lead Master plus Output Master controls.).
In comparison the Softube plugin reproduces this typical Silver Jubilee character very well, for my taste it even sounds much better than my own one ever did. This glassy treble scratchyness, which I also never liked on JCM's, is still existing, but at the same time is also has some decent sweetness, which I hardly noticed in reality. Nice programming job, obviously.
The Silver Jubilee never will become one of my favorite Marshalls, but the plugin itself is well made and also in comparison most probably the most authentically sounding Silver Jubilee simulation, which I have heard up to now.
If you like these - sort of hot-rod JCM800 - tones with some additional features, is a personal question.
If you do, this plugin will do the job excellently.