Sounds similar to the SamKnows Whitebox, which is a MT7621+MT7603+MT7612 router from which they run their speedtests and monitor various metrics. They don't act

Sounds similar to the SamKnows Whitebox, which is a MT7621+MT7603+MT7612 router from which they run their speedtests and monitor various metrics. They don't actually run clients off those radios, they just scan and sniff. I don't think regular consumer is their target audience however, they seem more geared to ISP's and government agencies who need performance data over a large amount of connections. I suppose the problem with wanting to build a small device that does this, is finding the balance between cost-effective and actually being able to pull off 1gbit throughput on it. Of course, this all assumes you were going the repurposed hardware route as opposed to design from scratch. Doing it from scratch would have it's own costs and pitfalls. (Board design, manufacture, licensing costs, etc)