Let me answer: the SiliCoil is my favorite brush-cleaning tank by far. The soft coil doesn't destroy and cut up my brushes like the plein air tanks or the no-tank method, which does not clean my brush!
Silicoil with a Ball Mason Jar
I understand the problem with going to a classroom and transporting your brush cleaner with you. The complaint by some - but not all about the SiliCoil is that it leaks in your paintbox when driving. Some artists will take Saran wrap and put a couple pieces of saran wrap where the top gasket or the top lid goes and then put the lid on and use it as a gasket. Another solution might be to put less cleaning fluid in your glass; a third solution is to find a way to leave your cleaner at the studio.
At home, I like to take a medium-sized Ball Mason Jar and remove the coil from the smaller SiliCoil container. I stretch and expand the SiliCoil to fit the medium Ball Mason Jar. Therefore, a year later, I emptied my Ball Mason Jar brush cleaner. I've removed 7 inches of solid paint at the bottom because the paint settles and goes to the bottom, leaving the top clean each time I return to paint.
Or the Canister Tanks: Not the Best Option
Another choice for cleaning your brush is with the plein air-metal canister tanks. These have a flat shelf inside, and the cutout holes seem to destroy my brushes. Cut and ruin my brushes. I may not have a solution, but that's not an option now. Something that helps tremendously is to use a rougher rag, and it takes more pain off. Therefore, I do not have to use the brush tanks. Then you don't have to use a paper towel as much.
Hence, I like the blue surgical rags, not the ones that are sealed and ready for surgery, because the big bag is very economical for $20 a get-a-year supply. I'm cleaning my brush with that. I don't hold it. When you have the paint rag in your hands, you get paint all over you and your clothes. I fold it in half. I put it on my table, and I never touch it.
This also means when I wipe my brush off, I wipe it off in a clean spot. You do know when you take the orange-reds and mix them with the alizarin and the blue-reds. You wipe it off on your rag; you remove paint on your rag, but you have the orange-red mix with the blue-red. You may drag your brush and make it dirtier than before you wiped it off. It may seem a little excessive, but if keeping your colors clean is the goal, the rag would do that.
I've always thought of cutting up the silicone oil and putting in a larger transparent mobile plein air tank and seeing if I could get it to fit into that now if someone could tell SiliaCoil to work on their top, we'd be home free.