Unfortunately, I didn't get a chance to do the before/after demo recording today because I still need to install my DAW software onto my laptop computer (I had to do a reformat/clean install recently because it had been running very slow lately), which I will be doing tonight, hopefully I'll get a chance to do the recording tomorrow, but, I did manage to get the three new valves installed in the Marshall amp and give them a tryout, first impressions is that the Marshall Amp sounds a lot smoother with the new valves installed, especially the overdrive channel, I can turn the gain up all the way and it doesn't get all flabby in the low end like it did when the old valves were installed, it sounds much more like a Marshall amp now, and the amp definitely seems to like the new valves, anyway, I like the sound of them so they are keepers.
The clean channel sounds really good, especially with some reverb dialed in too, definitely worth the money I paid for them, so I'll be buying more of them in future.