Here are the benchmarks that I was able to find that can detect Direct-IO disks.
All the test were done with WinRamTech 20GB NTFS RAMDisk with the rig in my sig but at stock (2.67GHz)
Anvil's Storage Utilities
Version: 1.0.51 RC6
Notes: Needs at least 1GB free to run
Notes: Results over 4GB/s loops back, but still seem in line with other tools
Notes: GUI can only display 6 digits (up to 1GB/s), but can copy the raw results
Notes: Still learning how to use it
I'll wait for some feedback before starting to test all the others RAMDisks.
In the meantime I'm interested in testing the effect of different file systems, RAM timings, RAM speed, hyperthreading off.
Maybe I'll try those same thing with Win8 to see if it makes any difference.