I just spent a weekend driving almost 1,000 miles to compete in an even that involved all of 7.5 minutes of competitive driving--but along the way I found my new phone was capable of doing just about everything I find great in the latest generation of in-car, OEM navigation and infotainment systems--and when I wasn't driving, I was carrying it around in my pocket.

Given that my phone (a Samsung Galaxy S II, not even the fabu-tastic iPhone 4S with Siri) proved itself capable of flawless GPS navigation with voice directions; a driving mode that reads out text message and phone call alerts; allows me to dictate and send text messages, make calls, and search the web by voice alone; has Bluetooth built-in for calls and audio streaming; has a nicely-sized touch-screen interface; easily stores 32 GB of media; and is constantly connected to the Internet, I found myself wondering why I'd want to pay something like $1,000-$4,000 or more for a similar system built into my car.

The wonder grew when I considered that my phone can be upgraded any time I like. The in-vehicle system in any given car won't be, and even if it gets a software update somewhere along the road, it likely won't be upgradeable to new hardware. After a few years, you're left with some archaic hunk of obsolete tech unfortunately front-and-center in your favorite vehicle. This might make sense for the lease crowd, or even those with the means to just buy a new car outright every two years or so, but for the rest of us, what's the point?

For the cost of a phone I'd have bought anyway, a windshield mount, and a power cord to plug into the 12-volt outlet, I have a highly capable infotainment and navigation system that in many ways is more touch-optimized and user friendly than anything in a vehicle. The only real advantages the OEM systems have are tied to the hardware: seamless integration, hardware control interfaces, and vehicle data/configuration.

For many, those are key features, ones that can't be passed up. For others, the ease-of-use and familiarity of the phones would trump the sleek integration of an OEM installation. For me, a tech junkie with the perhaps odd tendency to eschew any such computerized intrusion into the architecture of my own vehicle, the add-on nature of the modern smartphone satisfies both desires: it's there when I want it and not when I don't.

Sure, many carmakers are working on integrating smartphones into their infotainment systems--perhaps having already seen the increasing irrelevance of an expensive OEM solution without that capability. But is it really enough to have access to a handful of manufacturer-backed apps or steering-wheel controls in place of the full functionality and rich experience of the phone itself? And why would you need to sync/connect/otherwise mash-up your phone and your car if your phone is your car's computer?

The arrival of Siri for the iPhone 4S and existing apps like Vlingo and Jeannie for Android make even the most advanced in-vehicle voice recognition functions pale in comparison, too. Of course, you can't use Siri to change the temperature in your car, but then, is it really that hard to push a button or turn a knob?

Given the rapid advance of today's tablets (many of which can do everything a top-tier smartphone can do) and phones, and the likely superiority of future mobile Internet devices like them, is there really any non-aesthetic reason to opt for the pricey built-in systems offered by any manufacturer? If so, is the aesthetic justification enough?

For me, the answer is a definite no. My phone proved itself to be just as easy-to-use (or more so), just as full-featured (albeit in different ways), and every bit as elegant a driving companion as any of the modern infotainment/navigation systems I've tested in the past year.

What's your take? Let us know in the comments below.