>>10409247Soap gets rid of fats and that's about it. It does nothing against dust, grime, smells not bound in fats and dirt unless you scrub every individual part meticiously.
Soap and water is enough for casuals. I'm very hardcore. My LEGO is pristine.
Look at this picture. It's second-hand LEGO from 2005, yet there's but a particle of dirt buried in the holes and crevices. All the dust you can see is my self-accumulated shelf dust, and that's fine.
>>10409265Thank you. Though I wouldn't recommend an ultrasonic just for LEGO. The actual reason I do it is because it's cheaper to experiment on LEGO than on the very expensive things I actually have those cleaners for. Ultra-clean LEGO is just a really nice by-product.