Miners care a lot about ROI. FPGA seems too over priced, 4-6K per unit.
Mining with FPGA=Snakeoil?
At the current rate my ROI for my rig is 3 years.
A FPGA even with the current available not profitable bistream is 1 year but indeed, the warranty period is ridiculous.
You based on which coin or algo? We need to understand when it comes to crypto investment or mining, it pretty much the old wild wild west.
Full of scam from every corner, be it dodgy ico, mining software or hardware.
IMHO, FPGA is just a subset of gpu mining.