The only issue I have is that it booted the instance and needed immediately to do a software update .. that's a bit of a drag, I'd be happier if the base instances were already up to date before they get configured/cloned .. but no big deal, really. ( * -)
I'll use it for some ports and see how things go .. kudos to the icebergs.io team for making it pretty smooth to get a new Linux developer workstation set up easily enough ..
EDIT: (- * ) Actually .. this is a big deal for anyone trying it out - the update occurs and then the machine reboots, and then of course .. you lose your instance on the free-tier account. So if you want to use this for free, don't bother doing an update and definitely don't reboot the instance thinking you'll get back an upgraded machine. Apparently thats only for paid users.
EDIT2: Well, 5 minutes after finishing the software upgrade and accidentally hitting the "Restart" button without thinking, I'm left with a hung instance and seemingly no way to get the machine back to life. In case anyone from icebergs.io needs to know, the instance name is late-firefly-372, and all I did was log in, do the required software update, hit restart .. and wait .. and wait. The instance still seems to be responsive, but just not rebooting - some of the windows I left on the screen prior to the reboot appear to still be reacting to mouse events (the VNC config window checkboxes work), but the DE is dead and gone, and the machine doesn't seem to be letting me do anything .. thought I'd report it in case others run into this issue. Don't do the update and don't reboot! :)