Has worked great for me
I've been using the latest release of Mach3 3.043.022 (gota fix my signature) with the Mill Mach Steel Blue screen for about a year now. This latest version uses mach pulse driver 5.50.
On my PC with the Tormach ver. of Mach, I would typically see 8-10uS of Max variance during DriverTest. The latest driver version is solidly at 5uS...your milage my vary The Mach3 change log mentions many fixes since the Tormach release.
With this release and some parameter changes, I have run my 1st generation machine at a 105 IPM, all axis test for 3 days no stop. I checked the Work Offset position several times and it never missed a step. I backed it off since then to 85 IPM and has been trouble free.
Tormach PCNC1100, Mach 3 R3.043.037, MastercamX5 level 3.