In our office we have relatively poor ADSL connectivity (4-6 Mbps - I know some people here have far worse though). We currently have two ADSL lines linked together via a Draytek router and do OK. However I'd like to think about adding a third line and that goes beyond what the Draytek can do.
So I'd like suggestions for Linux distros which could replace the Draytek and do some half decent load balancing (and possibly caching for eg Linux and Windows updates etc) across multiple connections. It would need to be able to handle a number of VPN connections too (PPTP unfortunately but that's determined by the other end points).
I'm not interested in rolling my own - it needs to "just work" in the way that the Draytek does.
ClearOS and pfSense are on my radar although I have no experience of either. Any other suggestions or advice?