We had 10 such boards, good for millions of dollars in hardware, and a small team to keep it running.
These platform were mostly used by the firmware team to develop everything before real silicon came back. It could run the full design at ~1 to 10MHz vs +500MHz on silicon or 10kHz in simulation.
After running for a while, that FPGA platform crashed on a case where a FIFO in a memory controller overflowed.
Our VP of engineering said that finding this one bug was sufficient to justify the whole FPGA emulation investment.