No exact experience, but I have some thoughts.

If you run two separate drives you run two separate file systems. I think that would be an advantage but I can't give a plausible reason why exactly.

Splitting things between the two separate drives is likely to give advantages if you say ran two virtual machines at once. In that case I'd keep one on each drive. I don't think generally putting the system on one and the virtual drives on another will make a lot of difference unless you are running low on RAM and the pagefile starts getting used a lot. In that case you have bigger (easy to solve) problems.

If you run striped RAID0, I think the main performance increase you will see is reading large continuous chunks of data. I don't think it helps seek times etc too much.

All my 2c