My wife and I each picked up a Razr Maxx in the recent VZW BOGO promotion. She opted for a silicon case at the Verizon store. I went with the Otterbox Commuter. Some thoughts...
() Looks. My wife's "pink," (more "fuchsia" actually) case is a stunner. I would have gone with blue (the only other color available at the store) had I purchased one. Semi-transparent, it looks very nice. The Otterbox commuter, of course, is basic black and effectively conceals the fact that it's a Razr. Fine for me but I must admit it doesn't make much of a fashion statement.
() Bulk/weight. The VZW silicon case adds very little bulk and minimal but still barely noticeable weight. Still fits in her zipper case without a problem. The OC, on the other hand, adds significant bulk and weight. Not surprising, of course, given the double layer protection it affords. I can still fit it into the little Lowepro generic zipper case (designed for a GPS unit) I carry but only barely. Haven't seen the Otterbox Defender in person but for me, at least, the Commuter is as bulky as I would want to go and strikes a good compromise between bulk/weight and protection. The Defender provides a hard plastic screen protector to the package and a combo holster/stand for the phone. Otherwise, the basic design of the two appears to be the same.
() Protection. Well, there's no comparison of course. The silicon case will provide basic protection for a fall onto a solid floor I suspect. Nothing more and you may have to replace the case. The Otterbox is a two-piece case: an inner rubberized stretchy silicon case and a thick hard plastic shell. I suspect the phone could substitute for a puck if you're playing hockey. In addition, the OC includes silicon covers for the power/hdmi and audio out ports. Highly protective but a bit of a PITA to open/close/keep in place.
() Installation and Removal. The VZW case is easy to work with. Put it on; take it off. No problem. For the Otterbox, it's worth watching the video on their website. And tellingly, the video demonstrates putting the case on. It doesn't deal with removal. Be prepared to wrestle and with it. But it ain't coming off by itself; you can be sure of that.
Bottom line. Looking for excellent protection short of the cocoon provided by the Otterbox Defender, the Commuter is an excellent choice. And it's one of the few choices available at this point designed specifically for the Razr Maxx. Rough conditions might call for the Otterbox Defender with its separate stiff plastic screen protector. And the combination holster/stand may appeal to some. I prefer a naked screen and am willing to put up with a separate zipper case when I have the phone in my briefcase to avoid a "stick on" screen protector. I'm still a little envious of my wife's less bulky option, less weighty option but better protection don't come free.
Looking for a high quality and attractive relatively stiff silicon case? The VZW offering is a good one. Less expensive options are undoubtedly comparable but the convenience of viewing and picking it up at the store won out over saving $10 or so. Preserves the look of the Razr Maxx with little added bulk. Adds some color and is far easier to remove and reinstall than the Otterbox.