As UP says, "Suunto=conservative"
The algorithms in the Suunto and its parameters have been well-tested and the RGBM is arguably the most advanced and well-founded model for avoiding DCI. That said, for recreational diving, a good set of tables, a dive plan, and diving the plan does exactly the same. Also, within recreational limits, most
algorithms are about the same, however, the level of conservatism is different between manufacturers.
The Mosquito won't have you paying for a fancy case, and can easily become that BC-pocket resident backup in the future when you decide you need a super-duper trimix, heliox, 5-cylinder-air-integrated, dual-redundant, develops profiles on the fly, handles pure 02, ya-de-ya-de-ya-da computer in a couple of years. The wrist-mount Vyper is a little larger, easier to read, but otherwise very similar to the Mosquito (features and price). Choose the size and controls that make sense to you.
Suunto's Dive Manager software is freely downloadable from their website;
http://www.suunto.com/ Once you have it, you can simulate dives with any of their models and see how the screens display information. You can also download the manuals for any of their dive computers from the site to see if the buttons work in a way that your brain can understand. The fanciest computer in the world is little more than another entanglement and distraction hazard if you can't make use of it without thinking.
No matter what brand you select, I would
strongly recommend user-replaceable batteries! Too many people moaning about being without their computers because they had to go back to a far-away place for a new battery.
