Probing is supported, but of course the usual warnings and disclaimers apply. Probing may momentarily subject your monitor/panel to sweep frequencies in excess of its rating. The cautious may wish to turn off the monitor while the probe is running. In CRT mode the driver may produce video timings inadequate for your monitor, handle with care!
As with many integrated designs the speed of the graphics operations depend very much of the refresh rate you use. Higher refresh rates yield lower performance.