While the Model 98 Custom isn't a great tournament level marker, it can be upgraded to be suitable. Upgrading from the single trigger to the double trigger increases the rate of fire about two-fold. I would only recommend this upgrade if you are planning on playing speedball. However, there are a few downsides. The trigger is Quite expensive, for about $.20 of plastic. And speaking of plastic, the triggers made of it, which doesn't provide for the best durability, but then again, how much beating will your trigger take.
Conclusion:
Increases your fire rate, yet expensive. The trigger is a great addition, but don't waste your money unless you plan on playing a lot of speedball.