Conclusion
From an objective standpoint, Ocean is in many ways what Sidekick 3 wishes it was. It's smaller, lighter, and faster than SK 3 while also being more feature-rich. Helio's data speeds (over Sprint's EV-DO network) are fast enough to make HTML Web browsing enjoyable, and their GPS-enabled applications add locative data to the mix. The plethora of Email and IM options, along with MySpace mobile, appeal to the 24 and under market while also giving Ocean some cross-marketing appeal with the "hip at heart" professional set. While Ocean's size and style was a negative for me, plenty of other folks may well love the black and silver matte rubber finish.
From a personal standpoint, Ocean just isn't for me. It's simply too bulky for me to carry around on a daily basis, and I think the dual-slider form factor is overkill. Ocean's dedicated dialing layer certainly will make life easier for many of its users, but I'd prefer a slightly more complex button layout in the name of a slimmer overall design. The time I've spent with larger, thinner smartphones like the Motorola Q and HTC/T-Mobile Dash showed me that I prefer a device with a bigger footprint but thinner profile and lighter weight. That's just me.
That being said, given Ocean's overall bulk its QWERTY keyboard is just too small and cramped. Not unusable, just too small. The lack of personal information sync is also a deal-breaker for me - while I believe a solution is in the works, as a Mac owner I know that my solution will likely come well after an as yet unreleased PC solution hits the airwaves.
Bear in mind, whatever your initial impressions of Ocean, that this is a first-generation device built from the ground up. It's going to have bugs and quirks, but those will be ironed out in time. Ocean basically represents the next step for Helio, so look for it to improve in the coming months via subtle firmware upgrades and more dramatic new feature and application releases. While Ocean likely won't change or be replaced for awhile, it's more than reasonable to expect the device's functionality to expand; data synching, customizable Web searches, an "active" home screen ("Helio on Top" is actually available for Helio's other handsets), and more GPS-aware services come to mind as features that could make Ocean a more and more attractive solution well before we see another entirely new handset from Helio.
In sum, if you're a Sidekick user, MySpace/IM junkie, or gadget fiend looking for your next fix, Ocean is well worth a trial run. Power users used to full smartphone functionality and style-conscious techies who think "thin is in" may want to pass. At an introductory price of $295 with a two-year contract (various promotional discounts are available), Ocean is one of the most expensive handsets currently subsidized by a U.S. carrier. On the flipside, Helio's "All-In" plan provides unlimited data usage along with varying levels of calling minutes at competitive monthly rates (as of June 2007, $65/mo will get you 500 anytime minutes with free nights and weekends). Helio does offer a 30-day "Happiness Guarantee," so you could always get one and take it for a one month test drive before making up your mind. That's what I did.

