Full wave AC Voltmeter Vs True Rms Voltmeter
If it is a pure sine wave, yes. Harmonic distortion figures of 10% on power grids are not uncommon though, so you need to take into account that the reading may be off when you intend to perform a very accurate measurement without a true-RMS meter. 
It is definitely going to be off when it's clipped. An analogue meter measures the average value of the rectified AC voltage , which is 63.7% of the peak value in case of a sine wave and calibrates this value to the RMS value (70.7%). So your value will be overrated. With digital meters its more complex, nevertheless they will be off as well.   
Maybe not relevant but a full-wave meter has a higher sensitivity (kΩ/V specification) then a half-wave instrument. For low-power circuits that could be a disadvantage.