I have a collection of about 20 multi-tools from almost every company, Leatherman, Victorinox, SOG, Gerber, Wenger, etc, and I would say out of all of them Gerber's are my least favorite.

I do have the Gerber 600 series that you are talking about, along with the original gerber multi-tool. Aside from the one-hand "flick" opening feature, there isn't much else I like about it. Quality and workmanship is not even close to any of the other major competitors. Design is somewhat of a hack job, tolerances are loose, and just the overall feel of it makes it feel more like a kid's toy than a precision tool. I have a feeling if I tried to put it to use, I would probably break it in a short time. However, if you are looking for the stilleto type out the front opening feature, they're the only company that makes that style.

I do have a friend that loves gerbers, but mainly for the ergonomics over functionality or quality. For some people it's just more comfortable for them, and they're willing to live with the other shortcomings.