I think parrying for fighting games seem to be the most accurate and fun. In almost all cases the 'window of opportunity' to parry a move in fighting games in general is so miniscule and so small you don't get any wiggle room for error. In addition to that, some games such as the VF games in general have the most accurate and difficult parrying system to master since you have to take into account for all the high, mids, and low parries you need to do! Truly separates the men's from the boys. As far as other games go when it comes to parries (non-fighting games), they are WAY WAY WAY more lenient when it comes to the 'window of opportunity', I mean my goodness the arkham games are a perfect example! You can purposely miss time a parry, be inches away from the enemy and it'll still register causing batman to bounce to the target. lol