Teltonika RUT500

Has anyone ever used this for PLC-PLC communication?
It is a 3G router from a company called Teltonika. I see quite a few competitors using it mainly for its low price.
I read that it has VPN functionality which is what we want it for.
I need to setup Ethernet communication between 4 PLCs. One will be connected to an ADSL landline and the other three to 3G routers.
For the 3 stations I guess I could use this router. I read that this router can also connect to the internet using a WAN port, so no need of a GPRS connection if a landline is available.
Can anyone confirm that I can use this hardware to setup this netword using VPN?

This setup is alternative of using Siemens Scalance S612 coupled with M874-2 Gprs router.

Today I did a test, setting up two RUT500 as a VPN server and client using OpenVPN. It worked like a dream, not having to use static IPs at any point. I even setup my PC as a VPN client and connected to the RUTs from another location. I used a S7-1200 to test the connectivity with TIA portal using the VPN. It worked perfect. I used the OpenVPN in bridge mode.

The most amazing thing is that it costs a third of the price of a Scalance equivalent, and it is an industrial product.