While I have a carbon fork on my cross bike, I have a Spicer rigid ti fork on my single speed mountain bike and absolutely love it. With disc brakes it pulses a bit during hard braking, but so does the Airborne carbon fork on my CX when I use salmon pads. I mainly went with the carbon fork on my cross bike because I was able to get one for 1/3 the cost new off of ebay and figured that the carbon might absorb more road vibration when using it for road training.

I've seen a few people with Sibex ti forks on their cross bikes at local races and would definitely consider one for a dedicated cross race bike.