For example, the VCU1525 can make a decent profit even while mining Myriad-Groestl (Baikal X10 ASIC), so even competing against a dedicated ASIC, the FPGA can still mine with profit, although the ROI will not be maximized (ROI when competing against ASIC's is 1-2 years; ROI when mining non-ASIC coins is 50-150 days).
any idea where one can easily buy a VCU1525? digikey has very, very long lead time.