Dual WAN Routers

Lately more and more routers are available with dual WAN ports (Cisco, Linksys, and Sonicwall are the three big ones I've found). These are extremely attractive compared to the price of a dedicated pfSense machine that can handle the sort of traffic I want, but I'm curious how well they perform and whether anybody has any experience with the different brands. Round robin instead of fail-over load balancing is really what I want, but if we're going to buy new hardware, it would be nice to get the best value too, but I can't find any reviews that really highlight dual WAN capabilities.