In those price points you won’t see 20+kh Cryptonight and 17GH/s Keccak

You’ll also be dealing with older chips - 28nm variety Xilinx 7 series.

But - you can get performance on par with similarly priced GPUs (at 10% of power)for most of the discussed algorithms. And that’s from a relatively new platform that hasn’t had near the level of optimization. I hesitate to give exact specs yet because things can change between engineering samples and shipping products.

Overall if you have $500 to spend and want to get into FPGAs you can do it profitably, but if you have $5000 you can participate much more profitably $ for $.