This brush simply isn't powerful enough to break through the sort of stubborn grime that settles into corners or grout. You're better off with an old toothbrush and some elbow grease.

I just love this scrubber. I easily cleaned my grout lines, where before it was a shoulder breaking challenge. I'm probably going to buy another one! I thought it might not have enough power...but this is a case where I was happy to be wrong.

Saw this advertised on TV -- found it for a great price on Amazon (big surprise). It's a little powerhouse, and, so far, hasn't been real hard on batteries. A lot of the floors in our new-to-us home are tile -- with incredibly old, never-before-cleaned grout, that I've recently discovered isn't really brown, it's gray. It's a slow process, more the fault of the dirt build up than the cleaner -- 30 years is a long time to go without a good cleaning. This is the ONLY thing I've found that will remove that ground in, built-up grime; believe me, I've tried everything, right down to wire brushes. My biggest difficulty is letting the scrubber do the work, instead of trying to apply the usual ton of elbow grease. I wish it had just one more, smaller soft brush, but am quite impressed nonetheless. My husband has even used it on the sink, faucets, etc., and was pleased. Can't be beat for the price, that's for sure. Would highly recommend, even though the color combination's a little jarring.

cleaning my bathroom with my tooth brush would be quicker and more effective - complete garbage

Great product. Wish they made a giant version for the floor. Be careful around baseboards or painted walls as it is so powerful it will take the paint off.