Benchrest shooters use Speedy's method as barrels are cleaned after every 7-10 rounds. I have cleaned using that method for decades on my short-range benchrest rifles. I know that this method will not work on large cases where 60+grains of powder are used.
I have not seen those solvents do much for carbon removal, but are great for top-layer copper, and I have every product the company makes. Good bronze bristle brushes do the work as the copper is gone by the time I have removed the carbon, Dewey and Pro Shot brushes are good for 100 strokes max, with the most aggressive use of the brush being 60 strokes and less. Tipton has a bronze bristle brush with 30% more bristles but only comes in a three-pack whereas I usually buy Dewey and Pro Shot brushes by the dozen. Softer bronze bristle brushes are just good for exercise unless you load them up with JB. I have Hawkeye and Teslong bore scopes.
Again, get a Teslong bore scope, and discover which Cleaning methods work best for you! Methods and applications will vary between barrel types and quality. For instance, a Remington 788 in 22/250 will vary greatly from a Hart barrel in 22/250.
Monitoring carbon fouling is one of the best uses of a bore scope, with you adapting your cleaning methods to the particular barrel's attentive needs which vary from barrel to barrel.
Gunsmiths and Barrel makers are NOT HAPPY with the fact that shooters are getting Bore scopes. There is a learning curve in knowing issues of what you are looking at in a barrel vs what is affecting accuracy. Every gunsmith should examine the chamber before removing it from the lathe after chambering, and the vast majority do not. The gunsmith should examine the barrel before chambering, again, the vast majority do not. The customer then finds out about SERVICE AFTER THE SALE from that company/gunsmith. Gunsmiths do not have time to deal with Nitpickers who are looking for perfection over issues that are of no consequence., but chambers that are "ringed" where a reamer flute picked up chip weldment make for some ugly chambers. Also, you can see if the chamber was cut crooked where the leade angle was cut more on one side than the opposite side causing MAJOR accuracy issues. Bore scopes raise the bar in QC.
Monitoring throat wear, and fire cracking using different powders is another fine example you will see. R#17 and all of the N500 series, H4895, IMR XBR 8208 are all very aggressive in bore wear, which can Also be verified by monitoring the COAL to the lands.
When you are shooting a cartridge with a High Heat Index powder that is normally shot out in 800-1100 rounds, the wear pattern is amazing. It is also amazing how some barrels will shoot incredibly that look like a sewer pipe, but like throwing a light switch, they just quit shooting well. So, with the bore scope, you have a fighting chance of being prepared for the barrel to quit shooting well, with a backup barrel ready to screw on or at least have a barrel blank on hand so you do not have to Wait for one to be ordered. Be aware that when YOU send a barrel to a gunsmith, they usually chamber it, Quality control of the bore condition is on YOU, and problems with accuracy and copper fouling are also on you. These issues of quality control are madness to deal with when you realize that the gunsmith did not give a rip, nor did the barrel maker. Barrel makers vary greatly in customer service after the sale, and you can take that to the bank. I order my barrels, examine them, then send to the gunsmith. Issues with a rough barrel, a barrel with inclusions from the foundry, or barrels that have a screwed-up rifling, missing or thinned rifling are addressed before the gunsmith chambering the barrel. If you think that top barrel makers do not have barrels escape their inspection process, you are grossly mistaken. Also, there are different levels of production quality between the top barrel makers. My greatest concern with Cut rifle Barrels is how rough they are. Everyone has their favorites, and mine are Krieger and Brux cut rifle barrels...just my favorite. I have shot out a lot of Hart button rifle barrels over the years, also. There are some really good relatively new rifle barrel makers out there right now, Meuller in particular that I have used.
I have shot out a lot of barrels, with only finding half a dozen or so barrels that had BAD production issues that were missed at the factory. Each one of those bad barrels cost me a minimum of $1000 and a year's worth of aggravation in getting that barrel replaced, and this was the reason I got my first bore scope. The shock in my cleaning methods was a bonus.