Small office setup, best sync app

Hi
My setup is as follows:
2 x windows 7 laptops
WD mycloud 2TB
Cat5e Ethernet cables
Netgear gigabit router N600
All connections are cables

We have a small office doing basic 2d autocad drafting from either laptop. The initial plan was to store all data on the nas and work from this. The file size is generally less than 2mb. However this nas is far too slow and temperamental. File transfer speeds vary from 5mb/s to 80mb/s, usually closer to the 5. It is really inconsistent.
Initially this was fine, but there is now significant lag when working with files stored on the nas. Just a few seconds waiting for commands to kick in, but it is painfully slower than it should be and it adds up by the end of a day.
I can only think of 2 solutions:
1. store copies of the files on each pc, and work from these. This would require some kind of live sync software to automatically sync the updated data between the 2 laptops and the nas.
2. sync both laptops, and just have scheduled back up to the nas.

Which setup is the simplest?
Do you have any better suggestions?

Of course this would include scheduled nas backup to external drive as an extra backup.
Any thoughts?

WD SmartWare should allow you to run scheduled backups for your main systems, but it will only store the data from the computers into the NAS and will not sync the computers themselves. However, most 3rd party sync applications that support NAS devices or network volumes should be able to accomplish what you are describing.

Regards, 

I use SyncBack SE, and there is a free basic version, but you have other PC based software doing what you want to do. It is capable of detecting changes on the laptop and tne trigger automatically the update on the NAS, and vice versa. You can also schedule the syncs in the background, define retention rules for changed and deleted files.