As noted above, the DS115j runs Synology's DSM 5.x (DiskStation Manager) OS, DSM 5.1-5022 Update 2 to be specific. So it has all Synology's standard bells and whistles.
Synology DiskStation DSM 5.1 Desktop
It supports 65 out of 75 total add-ons listed in its Add-on Package Center as I write this. So you'll probably be able to find the app you want to properly trick out your DS115j.
DS115j supported packages
Performance tests were run using our Revision 5 NAS test process on a single-drive volume with a 1 Gbps LAN connection. The firmware installed was DSM 5.1-5022 Update 2.
The DS115j's Benchmark Summary below shows write throughput between 65 and 70 MB/s and read between 70 and 98 MB/s. Not bad at all for a Marvell-based NAS.
Synology DiskStation DS115j Benchmark Summary
The DS115j is the first single-drive NAS we've tested since switching to the current test process last April. So the NAS Ranker isn't any help, since it groups products by test method before ranking. So I'll have to do a little squinting and arm-waving to put the 115j's performance in perspective.
I started this review by comparing single-drive NASes to top-end routers with storage features. So that's how we'll look at performance. On the left below is write throughput for routers tested with NTFS-formatted USB 3.0 drives connected. On the right we have File Copy write performance for all single-bay NASes we've reviewed. Note the router storage performance test uses the same Robocopy test method as the NAS File Copy test.
The DS115j runs neck-and-neck with Linksys' WRT1900AC router. It also significantly outperforms QNAP's entry-level TS-120. Note, however, the TS-120 was tested with the previous NAS test process that used a different testbed, so that could account for some of the difference.
File copy write comparison - routers and single-bay NASes
The read comparison shows the DS115j with a significant 10 MB/s lead over ASUS' RT-AC3200 and, once again, QNAP's TS-120.
File copy read comparison - routers and single-bay NASes
The take-away is that the DS115j performs as well or better than the storage features on routers costing from $50 to $150 more. And, of course, the NAS has many more features than any of the routers. The comparison against other inexpensive NASes is less clear due to test process differences. But test process difference or not, it's safe to say the DS115j soundly spanks Seagate's Central, which uses a Cavium SoC.
Today's top-end routers definitely compete with single-bay SoC-based NASes, including the DS115j, when it comes to performance. But if you're looking for features beyond basic file sharing and DLNA media serving, NASes are still the way to go.
At only $130, Synology's DS115j is quite afffordable. But I won't call it the best value in single-bay NASes until I test QNAP's TS-112P, which is on the way in for review.