I demoed Alpine's CarPlay-equipped aftermarket stereo, the iLX007, in sunny Santa Monica, literally next door to the Hotel California. Yup, the place from the Eagles song, where "you can check out anytime you like, but you can never leave." And that's an apt location to try out this stereo, which, unlike the Pioneer AVIC8000NEX, is CarPlay only, and thus iPhone-only. You could check out any other phones you like, but you could never leave your iPhone--unless you want to reduce your $800 CarPlay unit to a lowly AM/FM radio.
So any cross-platform households will need to look elsewhere. Pioneer's AVIC8000NEX system, which retails for a spendier $1400, has a whole separate interface you can use without connecting your iPhone. It's even got Bluetooth so you could use it with another phone, and CarPlay only comes up when you physically connect an iPhone.
Alpine went the other way. The iLX007 only works with CarPlay-compatible iPhones (that's the iPhone 5, 5c, 5s, 6, and 6 Plus), and since CarPlay requires a tethered connection, the iLX007 doesn't have Bluetooth. Without a connected iPhone, all you get is an AM/FM radio, and a display of the car's rear-view camera if it has one. But even with that caveat, I came away from the demo very impressed by Alpine's execution of CarPlay--the iLX007 fixed my biggest complaints about the AVIC8000NEX, which were trouble getting Siri to listen, and the overall cruddiness of the touchscreen.
Now that's a touchscreen
Alpine's 7-inch capacitive touchscreen worked a lot better. The Pioneer often wouldn't register my taps, which is frustrating even when you can do most of the navigation by voice. Alpine's screen looked good, even in the bright midday sun, and every time I tapped it, the tap registered right away. (Imagine that, a touchscreen that works when you touch it...)
My other problem with the Pioneer CarPlay stereo was summoning Siri. When you get an aftermarket CarPlay stereo installed, it comes with a microphone that's mounted on the windshield. (I've seen it peeking out from under the rear-view mirror and at the top-left of the windshield near the driver's side door.) Saying, "Hey, Siri!" when using the Pioneer stereo would bring up the Siri screen, but not the audible boop-boop of recognition. I'd wait for the boops, and the screen would time out, and I'd have to try again.
Luckily, the Alpine stereo has a Siri button front and center. I wouldn't mind it being bigger, but I'm very happy that it's there. Every time I touched it, there Siri was, with a boop-boop, ready to go. Navigating by voice worked just as well as it did in my drives with the Pioneer, which is to be expected. If you know how to phrase your requests to get the responses you want, you're golden, but sometimes if you ask wrong, Siri can't figure out your meaning. But at least with the Alpine, you know she's listening.
If your car has a voice-activation button on the steering wheel, the stereo installer can program it to be a Siri button, so you don't have to press the Siri button below the touchscreen. And the Alpine rep explained to me that you can use the "Hey Siri" trick here too, but it's your phone's microphone that's listening for that, not your car's. (And of course this has to be turned on in Settings > General > Siri.)
Thanks to the smoother touchscreen and Siri button, using the iLX007 is a breeze. CarPlay uses apps and data already on your phone, so you don't have to install apps to your car and worry about keeping them updated, or have to search the same addresses in your car that you already looked up earlier on your phone or computer. If your phone knows it, your car does too.
Who should buy this?
The iLX007 does have an AV input in the back, if you want to add other sources, but Alpine doesn't think that will get a lot of use. This is for people who want to use CarPlay and nothing but. If everyone who drives your car has an iPhone, it's ideal, combining navigation, music, and communication with a no-fuss interface that's as familiar as that one Eagles song.