MB techs don't use dial gauges to set wheel bearing - they'd be laughed out of the shop. You either have mechanics feel or you don't. I've never had problems with any I've done and I always check them after a bit of test driving.
Setting them with a dial gauge didn't give me any better results and it took a lot of time to set up with little or no benefit. Once you know how much is the right amount it's not that hard to reproduce those results. For those who aren't sure, or do this job once every 20 years, the dial gauge might not be a bad idea. Most people don't own a dial gauge though.
