With single flow & empty network:
Can saturate 2.5 Gbps with standard TCP & jumbos
Can saturate 1Gbps with new stacks & 1500B frame or
with standard & jumbos
With production  network,
FAST can take a while to get going
Once going, FAST TCP with one stream looks good
compared to  multi-stream RENO
FAST can back down early compared to RENO
More work needed on fairness
Scalable
Does not look as good vs. multi-stream Reno