Note that, as far as I'm aware, this works the same way multi-core CPUs do: you need multithreaded workloads to see the difference! In other words you can *not* download 1 single file at twice the speed using both connections simultaneously. But you could download 2 files, both at 2mbit/s, saturating both lines, each with 1 file. If that sounds like what you want, then a load-balanced router is probably the best way to go. That way all the machines on the router can benefit, and you're more likely to take full advantage of both connections that way too.
- Oshyan