Let me start off by listing the earbuds I've tried prior to these, so you see when I say these fit perfectly, I mean it! My ears themselves are of average size, though my inner ear seems to be larger than what's considered large, earbuds wise. Over the past year, these are the other wireless earbuds I've tried:
Samsung Galaxy Buds+
Bose Soundsport Free
Beats PowerBeats Pro
Master & Dynamic MW07 Go
Master & Dynamic MW07 Plus
Samsung Galaxy Buds Live
The Buds+ fell out no matter what size tips, the Bose fit decently, but can't use just one at a time. The PowerBeats fit, though they sounded tinny and muffled to me. The Master & Dynamics sounded great, though they too would start to fall out after maybe 10 mins of moving around at work. The Buds Live actually fit well, though the mic was covered by my ear, so it kept making the volume fluctuate when I moved, thinking it was someone talking or something.
The Vistas fit well, and they're locked into my ears. I can lean over, shake my head and they will not budge. While it's only been a few days since buying them, I wear them at work all day, so that's 8 hours of constant movement, to include walking, bending, leaning, and generally on my feet nonstop. The eargels themselves cover the entire bud, save for the back, where the button is on each one. It has contact with a good bit of your ear, plus with the hook, and the earbud part fits in snugly, so all of that lends to a great fit, without worry. Most earbuds generally have the same size speaker hole in the bud, though on the Vistas, the hole is much smaller, which gives more to contact your ear to keep it secure, without losing any sound quality, and also adds to the passive noise cancellation. They don't feel particularly heavy in ear, that I've noticed, though if you're accustomed to buds like the Samsung's, and other similar size, it'll be a noticeable difference. I will say that after a few hours, they can become a bit uncomfortable, though after my prior experiences, I welcome the discomfort because at least I know it isn't falling out!
They sound really good, the sound is crisp, and depending on your EQ settings, has some serious bass, be it punchy or boomy, whatever your taste may be. You'll want to download the Jaybird app, speaking of EQ settings, as there are 8 presets, plus it can create a custom one for you. The app also has a Discover tab (shown in the pic below), where you have access to tons of custom EQs the community has created. You can preview the community EQs as you're listening to content, download and save them for free. For the personal custom EQ, it plays 6 different tones, representing low bass up to the highs, and you adjust the volume slider to where you just barely can hear the tone. The one it made for me has a lot of low end, with the mids and highs just below neutral, though sounds great. Current EQ I'm using is called "Audiophile 4k", from the community EQs. Having had the Master & Dynamic MW07s and Bose before, these actually hold up well against them soundwise, in my opinion, though of course those 2 are high end earbuds, with a bit wider soundstage. These Vistas at $150 are an amazing value for that kind of sound, compared to $300 earbuds. The device I've listened to them on is the Samsung Galaxy S20, for reference.
Codec wise, it's only SBC, which I understand to some can be a deal breaker, though even with that, they sound better than some others I used that were AAC and aptX compatible. Has Bluetooth 5.0, which is handy for the extra range and better stability over some that are still using 4.2. Also note that there is no active noise cancelling on these, though the passive NC is really good as keeping the outside noise out.
The case, with the front facing you, is about 3 inches wide and 1.5 inches in length, it's very compact, easily will fit in a pocket. It has a rubbery type feel, matte finish, which is great. They say battery life is about 6 hours per bud, which of course varies on volume and use. So far I've been getting close to that myself, with the volume at about 80% between the buds and my phone.
Each bud has a button, which can be customized in the app to control play, pause, skip track, volume and such. At first I thought it was a touch button, since you don't actually see it, so felt silly when I realized the button you push is basically the whole outer edge of the bud, where the Jaybird logo is. It's a clean look that way though, with them being flush, so nothing sticking out.
All in all, if you're like me, having had issues finding earbuds that wouldn't fall out, these are definitely worth a look. Almost makes me want to shed a tear of joy, finally finding the "unicorn" of earbuds to fit my ears. They sound terrific, fit well, look cool (especially the blue), have good battery life and they're well known for being durable (IPX7 rated).