Linux router distro with support for ADSL2+ and WAN load Balancing.

I am looking for a stable Linux Router Distribution with support for ADSL2+ and Wan Load balancing capable. I am planning to build two PC-router with intel Atom Dual core, DDR3 1 GB of RAM. I need a Stable and powerfull Linux distro to power up this two machines and be able to load balancing or fault tolerance between this two machines. I found on wikipedia a list of Linux Router Distros which is very interesting. The ones that i like more are: Vyata-commercial License (most closes competition to Cisco) untangle-Free/Commercial addons (It looks promising) M0n0wall-Free (for Small embedded systems) Zeroshell-Free (Small business server) clearOS-Free (based on freeBSD) RouterOS-Commercial (for use with routerBoard) Does any one have experience with any of those Distros. Also wich one of those distros will address my needs of adsl2+ and Wan load balancing/ Wan fault tolerance. Since I plan to add an ADSL2+ PCI card to each one of my routers PCs. Resume of what i need: stable router OS Support for x86 architecture Support for PCI ADSL2+ modem Support for Load Balancing and/or Fault tolerance. Others: Web interface will be a plus but not needed. CLI interface with remote SSH will be perfect.

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