I've been using a Lumia 920 since earlier this year. Also on the Amber update and wouldn't change it for any other non-Windows phone - I don't need the 41mega pixel on the 1020, though the 925 would be decent if I didn't use the wireless charging. I've only had 1 small issue when it didn't seem to want to turn on, but holding the power button for about 10 seconds fixed that. The integration with SkyDrive is nice, plus despite there being less apps, I can still get ones for my Synology, some of the banks have apps (though I'd never do that through the phone) and where my wife's (and others) have frozen on having long message threads, mine has never tripped up.
It's one of the most stable phones I've had, and certainly in work we don't get many stability issues when people call in with problems. The Amber update added a few nice extras like Data Sense and blocking of SMS/Calls from selected numbers. There's also a Kid's corner so you can let the kids have access to selected options/apps if you so desire, without the risk.
The biggest issue for some people will be the screen size (e.g. if not editing documents too much then a 520 would do the trick, the 620 is basically the same innards but a larger screen. There's also the 1520 phablet 6" big enough?!
though it's not cheap unless you're on a large contract. Haven't used Lync on mine yet either.
Taking off my Lumia hat, most smartphones today can do 90-95% of the things most people need them for, and as I get calls from owners of all types, have a try in-store first