In Fallout 2, it can be upgraded with a recycling chip, doubling the magazine size.
Accurate critical hits over a long distance are the Wattz 2000's strongest selling point. However, attaining a critical hit effect that ignores armor can overcome this weakness.
For example, Enclave troops in Advanced power armor Mk II have 90% resistance against laser damage.
The general effectiveness of the laser rifle is diminished due to the fact that many types of armor (and therefore enemies) have high resistance to laser damage, and as such the laser weapons are rendered much weaker against more formidable adversaries. Having a very long range and acute accuracy, the laser rifle can be effectively used in long distance combat.