Boss, no flame here, but I'll offer this FWIW.
I have used Butche's, Montana Xtreme 50 BMG and BTE. The Butches and 50 BMG are amonia based, the 50 BMG being much more potent. I have never used Sweets but I expect that it lies somewhere between Butche's and 50 BMG. The 50 BMG works much better than the Butche's and the BTE is hands down better than the 50 BMG, in my experience. And I am talking forn the experince of rough Remington bores. Custom bores are much easier to clean, so I've heard.
My cleaning experience will usually go something like this.
Soak patch with BTE and push through slowly - it comes out black.
Repeat - it comes out black again.
Repeat - it comes out black and blue.
Repeat - it comes out deep blue very little carbon.
Repeat another 3 or 4 times until blue starts to fade. The bore is not clean yet, just getting down to the stuborn layer.
The bore is still wet from patching now and I put a nylon brush through it. I stand the rfile up on it's butt pad and put 2 or 3 drops of BTE into the muzzle. Place the rifle on the sand bags and stroke a few times with the nylon brush amd let it sit for 15-20 min
I put another wet patch through and it comes out deep blue again.
I repeat the process for another 2-3 times until the wet patch comes out pale blue. At this point it is 95% or better free of copper. I spray it out with Birchwood Casey gun scrubber, dry patch and continue to shooting unless I want to get it 100% free of copper.
I know you use a bronze brush to get the mechanical action. I don't know if you've tried BTE, but I would bet that it would be more effective than Butche's/Sweets and a bronze brush. I use a nylon brush to work in the the BTE on the stuborn copper and accelerate the chemical reaction. I dont use bronze brushes or brass jags becasue BTE will eat them up and leave false blue in the bore.
If I used Butche's/Sweets on my bores, it would take multiple hours to accomplish what I can accomplish in about 1 hour on a rough bore with BTE.
I dont have a bore scope (wish I did) but have had my bores scoped by a smith who says they are completely free of copper when I bring them, so I think I have a good idea of when my bore is clean.
The same smith has another very cheap, quick and effective way of cleaning bores. He puts a chamber plug in and closes the bolt on it. Then he sits it on it's but pad and pours pure amonia down it untuil it's full. He says it the chemical action is so strong that it bubbles up out of the muzzle. After about 5 min or so, he dumps it out, dry patches it, flushes with brake cleaner and dry patches again. That makes me cringe, but he says it works fine and he has a bore scope.
I am not a BTE salesman and have decided to move on tio KG-1 and 12 because I've heard a lot of good things about them. In fact, just ordered some from Midway. I'm expecting that they may be better than the BTE, but we will see.
No flames here, just my experiences. I have found that compared to BTE, Butche's and 50 BMG are mediocre cleaners and much more labor intensive. And in fact, after leaving 50 BMG in the bore for 30 min which I dint like doing with amonia. It showed a clean patch, indicating no more copper. When follwed up with a 20 min BTE soaking, a good bit more blue came out.
Cheers,
Mark