It really all comes down to your monitor.ini presets, which you can adjust through VMM. There is a way to get the best out of your PVM, and it involves using two crt_range values in your monitor.ini file, to something like this:
monitor "SonyProf", "PAL/NTSC Sony Profeel", "4:3"
crt_range0 15300-16200, 49.50-51.20, 2.000, 4.700, 8.000, 0.064, 0.192, 1.024, 0, 0, 192, 288, 448, 576
crt_range1 15300-16200, 59.95-62.00, 2.000, 4.700, 8.000, 0.064, 0.192, 1.024, 0, 0, 192, 248, 448, 480
This will choose 60hz range (crt_range1) modes for any modes up to 248 vertical lines, but default to 50hz range (crt_range0) for anyhing more (up to 288 vertical lines). I've bolded the relevant numbers in the modelines above because it is the key to making this work.
Every monitor is different, but those ranges are what I use with my Sony Profeel 20" PVM. Your PVM has a "QM" in the model number, which means it similarly was made for the antipodes (southern places like Australia), and also means it most likely/should take both PAL-like modes (~50hz) and NTSC-like modes (~60hz). Those crt_range values I gave are pretty trim because the Profeel get's fussy if you go too far away from 50 and 60hz. However, it is very forgiving for low horizontal frequencies, which is why I have given it a low range (15300) so I can get useful modes like 768x512@51hz easily (gives you a few extra vertical lines in windows that are really useful).
I also have a Sony 27" PVM(QM) that has a dead-spot around 55hz, but not as big as the Profeel's. I haven't done Groovymame with it yet though so sorry no crt_ranges for that.
Now, Obviously it isn't ideal for games like R-type that like 55hz, but Groovymame will do it's very best to make it seamless via software, CPU grunt and even skipping frames according to your monitor/TV's constraints. And Groovymame's best is pretty good.
If you want to find your own monitor's ranges through trial-and-error, try starting with these ranges:
crt_range0 15300-16200, 49.50-55.00, 2.000, 4.700, 8.000, 0.064, 0.192, 1.024, 0, 0, 192, 288, 448, 576
crt_range1 15300-16200, 55.01-65.00, 2.000, 4.700, 8.000, 0.064, 0.192, 1.024, 0, 0, 192, 248, 448, 480
Then test the various modes with ArcadeOSD. For the ones that don't work, note their vertical (in italics), and to lesser extent horizontal (bold) frequencies and trim the ranges accordingly in your monitor.ini. In VMM, be sure to click the box to update mame.ini. Then generate modes again/install/restart and try again, rinse recycle repeat, until you are happy with the ranges.
Most TVs that do both 50 and 60hz modes will have a dead range around 55hz. Not always: my Loewe Calida Blackline 100hz 26" in my vertical games cab handles 55hz well, but that has other issues.