Cut away guitars and dreadnought guitars generally have the same method of mounting the neck... For example... If you took a Taylor dreadnought and put it next to a Taylor cut away... they would have the exact same method of mounting... With that said, No.... in most cases neck stability isn't an issue.... You should never be worried about neck stability either way... If neck stability is a main factor in whether you buy a guitar or not... then you need to drastically change your playing style.... You should never break a neck at the mount unless you have completely neglected the guitar or have thrown it around an uneccessary amount... And that is to no fault of the manufacturer.... I will say, however, that Gibson SG models ahve been notorious for having weak neck joints... Since the body is thinner than the Les Paul... yet Gibson still chose to use the same mounting method... they are known to break at the neck mounting point when played in a touring type setting.... Also... you should take care when using bolt on type necks as well... They are sliiiiiightly more succeptable to breaking from being thrown around... However, Set neck guitars are more likely to be affected by atmostpheric changes...