Wherever you install the Sleek, you'll need to follow a few important guidelines. In the car, Wilson advises that you place the antenna at least 12 inches away from other antennas and at least 6 inches from the sunroof and the rear or side windows. The center of your roof is the ideal location, but drivers with smaller cars may struggle to find a position that matches the guidelines. Also, though the metal roof of a car is supposed to act as a barrier between the antenna and the Sleek cradle, you may experience some feedback if the parts are too close together. If that happens, you'll have to move the antenna again. What's more, Wilson advises that you install the cradle at least 8 inches from any passengers. That may be tricky if you drive a Mini Cooper.
Keep in mind that you'll need to keep your phone in the cradle if you want to get the boosted signal. That means you'll have to either use the speakerphone or invest in a wired or Bluetooth headset. Given the suggested 8-inch separation distance between your body and the cradle, you should not hold the cradle to your ear when in use. But if you're driving, you shouldn't be holding a phone to your ear anyway.
As with all cell phone signal boosters, the Sleek 4G-V is only as good as the base signal you receive. Remember that it's not a cell tower, so it can't create a signal from your carrier if one isn't available. It can, however, take a marginal or barely-there signal and make it usable. Indeed, that's how it worked when I tested the Sleek 4G-V in Guerneville, a rural area of Sonoma County, Calif. In the first test area, Verizon's LTE network was not available. Its 3G network only showed two bars on an iPhone 4S, whereas a T-Mobile Nokia Lumia 710 and an AT&T iPhone 4 showed only one bar. Though the Verizon handset fared better than the T-Mobile and AT&T phones, none of the devices performed particularly well without the booster. Text messages came and went without any problems, but call quality was poor if I had a connection at all. Likewise, data service was mostly unusable.
Fortunately, though, the Sleek 4G-V made a big difference. Moments after each phone was inserted into the cradle, it jumped to a full five bars. The T-Mobile Nokia still topped out at 2G (T-Mobile's 3G coverage doesn't quite reach where I was), but the Verizon and AT&T phones found their respective 3G networks. There was no change in text-message service, but data speeds increased to usable levels on the 3G devices. Naturally, data on the 2G T-Mobile phone was slow, but it was fine for sending e-mail or viewing mobile Web sites. Like I said before, the Sleek 4G-V is only as good as the base signal it finds.
Call quality varied by phone. I had no problem connecting on the AT&T iPhone 4S, but I still heard a fair amount of static and interference. It was suitable for touching base with a friend about meeting for dinner, but not ideal for a long conversation with my dad. Audio quality on the T-Mobile handset was somewhat better, but I had more trouble connecting and keeping the call once I had it. The Verizon phone was the best of three. It still wasn't spectacular, but it was enough.
In the second test area, I was just at the fringe of Big Red's 4G network near Petaluma, Calif. Like before, the Sleek 4G-V boosted the LTE signal to a usable level, and it maintained the connection through the trial period. Data speeds were slower than what I'm accustomed to in the middle of San Francisco, but they were an improvement over the 3G speeds I got earlier.
The Wilson Sleek 4G-V is not a miracle worker, so don't expect it to be. If you get no signal, it can't help you. It can, however, take a minimal signal of one or two bars and turn it into something useful. Even if your phone still isn't in top form (as I found), at least you'll be able to make calls, use most data features, and send and receive text messages. Of course, your exact experience will vary by device and by carrier, and you'll need to remember the product's design limitations. But if you're a trucker, you live in a rural area, or you just get crappy service in your inner-city apartment, then the Wilson Sleek 4G-V may be just what you need.