I use Purple Power degreaser/cleaner from Walmart. I use it on everything from under the hood, wheels, exhaust, to get bugs off paint, i just spray it on and let it sit for a few minutes (usually Ill spray the wheels and exhaust then wash the rest of the car !!!Unless it is hot out then it dries to fast and looks like crap!!! then I hose it off and wash the rest of the wheel with a mit. applying more purple power if needed. also this is in another thread of mine. I spray it directly on the wheel and the tire and it strips off the old nasty dirty tire shines and protectants then I re apply clean tire shine, it seems to last longer and looks better. and use a wash mit and for the hard to get areas i use a soft tooth brush and they come brand new clean. BUT!!! I must say from past experience if you have a anodized aluminum (my wife has a anodized red BOV from GFB) if it gets on there it leaves like white spots and they are impossible to get off so i just cover it with a plastic bag. Good luck hope i helped
Oh and I will answer your question for you too.... It should be fine to use the sonic scrubber the BBS wheels are tough and if i can handle a tooth brush it wil be fine. but look into both I think my way works out better for me and is cheaper than spending $10 on the scrubber plus money on the brushes and batterys. all I spend is 3-15 on purple power (normal sized spray bottle windex, black magic size for about $3 and I bought a 2 gallon refill jug for like $15 and it last forever. you can also dilute it but I always use it straight) and 1-3 for a toothbrush/detail brush