I read the thread and voted no, as I compared it to that of the M4.
Ultimately, however, it is all down to personal preference, and moreso, experience.
If you threw me an M4, or an AK, I would have to sit for 5 minutes and work everything out. They are both relatively self explanatory in that regards.
On the flip side, if you threw me an SA80, blind folded with gloves on I could still perform all the drills in seconds.
One thing you must remember, airsoft aside, is you are likely to be carrying the weight of that weapon system on your shoulders for days/weeks out in Theatre... I sure as hell would rather have the plastic M4 with boxes of 5.56 to support than the weight of an AK over a period of time.
Personal opinion, anything Bullpup (Particularly SA80)- Reason: Weight is all in the rear, and the trigger finger remains on the trigger for all weapons drills, which above anything else is safer as the weapon "should" remain pointed at the target at all times. Once you start flicking your trigger hand here, there and everywhere, weapon discipline soon goes down the toilet and you end up shooting your mucker in the crotch.
Ergonomics is more than just how quick you can change mags, its whats safest, and the most comfortable long term.