JayBird Gear's BlueBuds X are the company's top-of-the-line Bluetooth wireless in-ear headphone model, and they're one of the better pairs of wireless sports headphones I've used. Outstanding? Well, that depends on how good a fit you get, but I have no doubt that the folks who do get a great fit will rate these very highly.
What's impressive about the BlueBuds is how small and lightweight they are in comparison with other Bluetooth in-ear headphones. They share some similarities with the compact Plantronics BackBeat Go earphones, which cost less than $100 and have the same tangle-resistant flat-cord design with an integrated remote/microphone. However, the Plantronics' battery life isn't as good as the Jaybirds' and they aren't sweatproof (Jaybird offers a lifetime warranty for any sweat-related issues the earphones may encounter).
The one complaint I had is that despite their small size, they're still bigger than your average earbuds and depending on the size of your ear -- mine aren't particularly big -- I found that they had a tendency to create some irritation after extended use. For some people this won't be a problem, but when you jam the tips in your ears, the base of the bud (the hard part), which is a bit larger, might feel a little bulky. This wasn't a huge deal, and you can make adjustments to relieve any annoying pressure, but I came away thinking these earphones were comfortable but not supercomfortable.
To help you get a better fit, the BlueBuds come with three different-sized silicone buds and three "wings" that are designed to keep the earphones in place during workouts. There are a couple of different ways you can wear the earphones and it takes some experimenting to come up with the right combination to get a secure fit.
You can go with an over-the-ear fitting and then shorten the cord length so the cord ends up resting very close to the back of your head. You can also just let the cord dangle down from your ear as you would with typical wired earphones. You can choose to have the cord sit in front of your neck or behind it (most people will wear the cord behind their necks). This setup is better if you plan on making calls because the microphone sits closer to your mouth, rather than on the back of your head just behind your ear.
What's a little kludgy is the way you shorten the cord. There's no built-in shortening mechanism; you have to manually shorten them to the desired length using the two sets of tracks or guides that ship along with the silicone eartips. These almost look like tiny Lego pieces, so if you're into Lego, you'll have no problem setting this all up. But as I said, the pieces are small, and should the cord get yanked on really hard, the piece could very well pop out and get lost. While the whole thing works, it seems like the design could be better and easier for the average consumer to grapple with.
To be clear, the BlueBuds are designed to be jammed into your ears, and getting a tight seal is crucial to getting better sound with deeper bass; if you lose that tight seal, sound quality dips dramatically. As such, these are a noise-isolating model, and they do manage to seal out a good amount of exterior sound, so if you're worried about hearing oncoming traffic while you're running, they may not be for you. (The $50 Plantronics BackBeats 903+ sports earphones let sound in but they don't sound as good as this model, nor are they as lightweight).
To charge the earphones you lift a cap on the left earbud to reveal a Micro-USB port, which is pretty nifty. A cable is included for charging and there's an LED on the right earbud that lets you know the earphones are on and when they're charging.
My only other complaint about the design is that these guys just don't exude "premium." They have an all-plastic design with a bit of plastic chrome trim. The earphones also come with the same cheap-looking clamshell case that's included with Jaybirds' previous Bluetooth earphones. I've never been a fan of plastic chrome, but that's just me.
Despite their all-plastic housing, the build quality seems decent. However, I only used them for a week, so I can't really say how they'll hold up over time. But I would strongly advise stowing them in their case when not in use.
The BlueBuds' biggest feature is obviously their Bluetooth wireless-streaming capabilities. They should work with any Bluetooth-enabled device, including iOS, Android, and Windows smartphones and tablets. I tested them with the iPhone 4S, the Samsung Galaxy Note 2, and the iPad Mini.