Bit tight the connections. There are virtually no upgradeability. If you need more space, has to install cumbersome new disks or connect an external disk via USB. Expansion modules do not exist. It is more than a play DiskStation as a real station.
But an absolute disaster is the support from Synology. Since upgrading to DSM5.1 my station is stuck at a CPU load of 99%. Few processes seem to spin. The station is not on standby, yet ceases rumzulesen on the hard drives. These now breaks the backup process from permanently because something permanent changes to the plates.
Synology Support told me to turn off IPv6 support. When that did not bear fruit, I wrote back and asked for help. It's now three weeks ago - silent ever since. When asked no answer. The station has now become worthless electronic waste.
To play at home is to use Synology perhaps, in professional use includes a zero-supportete DIY solution not.