A good craftsmanship ranged weapon with the Unreliable Quality, loses it (if it has it, see p167).
A good-craftsmanship M36 Lasgun normally applies no benefit - since it is already Reliable (p167).
However, in the Overload setting the M36 Lasgun gains the Unreliable Quality (p175).
Therefore, in Overload mode, a good craftsmanship M36 loses the Reliable Quality - but does not gain the Unreliable Quality. Jams on a 96-00.
A best quality M36 on Overload would never Jam - a jam counts as a miss. However, technically the gun has the Unreliable Quality and so misses on a 91-00. Imo this is a little odd...
Common Sense would suggest that Best Craftsman should apply the same benefit as Good with respect to losing Unreliable and gaining Reliable (as applicable) - in addition to Jams counting as a miss.
Anyone disagree?