does it worth buy a mining rig FPGA? how much time we will need to get back the investment? 2 years non stop?
before the BFL ASIC announcement, I would have said yes, it pays off, now I would be a lot more careful.
Only time can tell how BFL will really perform with the new gear. If it turns out to be real, then all FPGA will be obsolete (for mining, they still hold a certain value of course). I personally changed my strategy and pre-ordered the BFL ASIC`s with half of the planned invest for the next months. The other half still goes into FPGA, but this is high risk. Maybe BFL is high risk as well. This announcement is game-changing and there is probably not a "one-and-only-fits-all strategy"
But the primary focus is probably not to make dollars out of the project but support the whole idea in some way. In the secondary focus, of course we all want to prosper ....