I purchased a Beretta Nano several weeks ago and wanted to share my experience with it. This won't be a detailed review - there are plenty of those with all the specs and comparisons to other micros. It's just my experiences and impressions.
Short version: LOVE IT.
I purchased it at the Tanner Gun Show in Lakewood for $405. This was the lowest I saw the pistol available; most prices ranged from $420-435. I am a medium-small guy with fairly small hands, and it felt great. Looks great at well - really nice-looking pistol. I had been planning to get a Kel-Tec PF9 when my brother pointed out the Nano to me. After some research, I decided it was a much better option.
My first shooting trip with it, I shot 140 rounds of WWB. It functioned 100% with no issues. Furthermore, it was a joy to shoot. When I mentally compared it to what it would have been like to shoot 140 rounds through a PF9... well, I was very pleased. The trigger pull is on the long side, but for a CC pistol, that's fine. It's not a bad trigger, just long. Because the pistol is basically a 9 built on a 40 platform, as opposed to a 9 built on a 380 platform, it's heavier than a PF9 but much more comfortable to shoot. The short sight radius makes it harder to be precise, and the small magazine means frequent reloads, but otherwise it's a perfectly fun range gun.
Before my next trip, I put on some rubberized Talon grips. They went on cleanly and fit well, except the small circle cut out for the Beretta logo was off by a bit. Not a big deal, and I'm sure it's hard to get those perfectly centered.
Second shooting trip, I put another 60 rounds of WWB downrange. Again, 100% functionality. Once, I had trouble seating a full mag with the slide down. A few moments later, I noticed the floorplate on the mag wasn't securely locked in place. Not sure if those were related, but once I fixed the floorplate the issue did not come back up (and hasn't since).
So at this point, with 200 rounds of FMJ at 100% functionality, I decided to feed it some JHP. Yesterday I went out for my third trip with the pistol, and fed it a box of 50 of Federal's standard JHPs. No issues at all, so I gave it 30 rounds of 147gr Golden Saber. Those were 100% as well.
At this point, after having taken it out three times, I gave it a good cleaning. So far, all I did was take it out of the box and shoot it. No clean, no lube, no locking the slide open for days at a time. The pistol now has 280 rounds through it with no malfunctions. I trust it and will be comfortable carrying it.
Other general notes:
-The sights are adjustable for windage only. The pistol shoots a couple of inches low, but as I received it was dead on for windage. That's certainly close enough for the distances appropriate for this weapon.
-The lack of a slide release is usually inconsequential. The challenges it presents are outweighed by the concealment/carry benefits. When shooting at Dragonman's, they called a cease fire and the slide was down. Both mags were loaded. So I simply pulled the slide back and held it open, stuck my finger in the ejection port and pulled the tab up from the inside. Not something I'd want to have to do all the time, but it took two seconds and wasn't hard.
-I really like the button to deactivate the striker, and the takedown mechanism. Takes five seconds longer than my Glock 19 (so - twice as long), but is safer without impact on shootability (unlike some stupid safeties e.g. mag safeties).
-I heard of some early issues with the Nano, but either Beretta has corrected them, or I got lucky.
I would have zero hesitation in recommending this pistol to anyone for whom it feels comfortable in the hand. It's a great little shooter, well-designed, reliable, and fun.