The Gridseed ASICs that can mine scrypt have been on the market for a few months already
The ASICs I was talking about are those which really CAN obliterate scrypt mining. Gridseed is in no way to do that. Just compare price to speed.
what is promised is minimum 250MHs for 15000 EUR
Counting a little we get almost a tale in performance to money - after <2 months for returning the full price start to make 20-24K USD a month.
I am not interested in Gridseeds, so I can't tell the price for a fully working unit. The web page you offered sells all the parts in separate. But price for a unit 4200$ for 8 MHs maximum is in no comparance. May be I am mistaking here and those units work much faster? But from what I see the bonus here is only size and power consumption which is rather low in comparison with GPU rigs of the same mining compability.
The numbers I found for gridseeds indicated approximately $2000 USD outlay for 3-3.4 MH/s scrypt at under 100 watts, or approximately 30w per MH/s, where GPU's require a minimum of 250w per MH/s. For 15000 EURO (or just over 20000 USD) that would buy 30-34MH/s of gridseeds available today. There is a possibility that other hardware may never actually be delivered though (but even if not, something else will likely arrive on the scene).
I'm not sure why anyone is interested in any of it while btc and ltc prices continue to fall...