Yes, I would buy it again, although that needs qualification. The biggest qualification is that I can't find anything remotely as capable for close to the same price.
PROs: It works (mostly), it's cheap, it can be made to work without too much effort with other OSs. (I primarily use Linux, but I can mount the units as windows share, or NFS, or use FTP. Don't see how anyone can complain too much about that many options.)
CONs: It's slow, even on a dedicated 100 mbit network.
DLink seems to have spent most of it development work on much smaller drives. Heat issues with larger drives have been going on since the beginning, and still don't seem to be solved. As long as I can go out and buy a 2 TB drive for $140, why in the world would I spend $400+ on a DNS-343 and stick 4 1/2 TB drives in it? DLink should spent a LOT (as in nearly all) time worrying about how to make the largest available drives work reliably.
It heats up at the drop of a hat. My second unit, which I still haven't determined if I'm going to return or not, boots at 44 degrees C, which is just 2 short of it's lockup point. I spent a week trying to get it to sync the drives, which requires over 25 hours. The only way I could get it done was to lower my household airconditioning to 72 degrees F, close off all the other vents in the apartment, and set the unit directly under the remaining vent. I did finally get it to sync, but now I can't load it for more than a few hours at a time without having it lock up. If I didn't have one unit running just fine, I'd assume it was a design flaw. Now I'm just trying to figure out if it's just a problem with this unit and if a replacement will resolve the problem.
For the record, I have two DNS-343s, both running 1.02A, RAID 5, and loaded with 4 Seagate 1.5 TB Barracuda drives.