Now with next MBS Plugins, we have already prepared a replacement class: WindowsTimerMBS.
This class can provide an action event on main thread much closer to the 5 ms target as you see in this screenshot:
Of course timer can only fire if main thread is not busy, so if you do too much code in action event, the next event may be delayed.
I hope this makes a couple of Xojo developers happy, for example if you want to measure values 100 times per second on a serial port.
PS: In newer plugins, the WindowsTimerMBS class got renamed to TimerMBS.