So I've played a bit with my Ersa nano, and so far I am happy. Here's a little mini-review.
The iron itself is smaller and lighter than I expected. (It makes me intuitively think that it's not suitable for soldering heavier connectors, wires to sheet metal, etc, but it probably has enough power to do those just fine, with a larger tip.) The cord to the iron is thin, light, and flexible. I love it!
The base itself is very heavy for its size, feels very solid. The small size is great for me, since I live in a small apartment and do not have a dedicated workbench and thus need to be able to stow all my tools away after use. The soldering iron holder is rubber, not plastic, and works rather nicely.
It heats up insanely fast. There's literally no reason not to turn it off when tinkering, because it heats up in the time it takes me to line up and flux the joint. Its default mode is one of pumping a LOT of heat into the iron when heating, so it heats fast and maintains minimum temperature very well. This mode does, however, tend to overshoot the setpoint temp by about 20C before settling down to the setpoint. For delicate things, it may make sense to use a microSD card to program it to one of the lower-energy modes that heat more gently, but don't overshoot as much (medium mode) or at all (low mode).
In practice -- bearing in mind that I have been soldering for decades, but have only ever done it with shitty 15 or 20W garden-variety soldering irons -- it seems great. So I can't compare it to other soldering stations, but so far I'm loving it. The quick heating means it's ready to go quickly, and responds very fast to touching the tip to larger joints. The thin cord is a revelation. My hand isn't tired after using it, as is the case with thick, stiff cords.
The only things I would improve -- and I'm nitpicking here -- are:
- The LCD is not backlit.
- The soldering iron's plug into the base station is actually the type of connector I normally expect to see only inside a device. (It is however, very well strain relieved.)
- The base station has no rubber feet. Only the friction from its substantial weight keep it from sliding around on the feet molded into the case. Not a real problem in use, just surprising.
- The manual is a joke. It covers the safety stuff, but none of the interesting features. For those, see the manual included with the programming software at: http://www.ersa.com/index.php?modul=download&cat_id=20
If you plan on using multiple tips, I strongly suggest getting additional ferrules (Ersa part number 3IT1040-00 for black, 3IT1045-00 for green), since they're a pain in the butt to get off a tip. Since they're only about €5, I think I'll get one for each tip I have. With a separate ferrule for each tip, changing tips takes just seconds.