sfx2000
Part of the Furniture
The difference with Portal comes when radar is detected. All other routers will drop all conceptions during the one minute CAC. Portal runs CAC on all DFS channels during boot, so can switch instantly to another channel, then run CAC on the vacated channel using its dedicated monitor radio without having to drop connections.
I won't say so much about Portal and their implementation - but if one is in a DFS area where radar might be a problem - it's probably an area where it will always be a problem... I personally haven't seen an area where that issue is intermittent - as such, there are other router/AP's that support DFS quite nicely...