so if the equipment arrived today you'd be earning about $500 a day, in which case you'd get back your investment in a week.
now here are the buts.....
*the difficulty in november will me MULTIPLE TIMES higher meaning you wont be earning the same income as now
*the risk that 'if it sounds too good to be true' ... it probably is
*with that, what promises or guarantee's do you have of a refund. EG do you know their street address and directors name(s).
*are they even in travelling distance to slap them with a wet fish if they dont forfil promise.
*even if they are developing units, how certain can you be of the date of delivery. do they even have a working prototype, or is it all still theoretical
100Gh gets you .44 btc per day, and for about the next 10 days ( 2 days ago it was .58 day, you should find a different calc).
my spreadsheet is estimating that by mid november, the diff will be approx 250M. at which time 400Gh will earn about .7btc per day.
400G delivered by mid Nov might make you about 30btc....then you also have to consider elec... 500Gh of 65nm chips costs me about 7 dollars day.