Choices....

What should I get?

$60 - CO2 500 FPS pistol - here

$45 - New Inner Barrel 6.03 and new Battery (better ROF) -
here and here

It's a very hard choice.

Personaly I would go with the 6.03 barrel and battery. 500FPS is a bit high for a pistol. And being CO2 it's probably a gas hog. And pistols arn't really desighned for range or accuracy.

I would go with a pistol for 2 reasons.

1. They are light weight and can easily be holstered onto a leg, belt, or under arm holster. Pistols are used in most building clearing tactics because they are semi-auto and most urban fields will require semi-auto indoors. Points are deducted for using automatic rifles indoors. This is because there may be times your dealing with a hostage situation and many many points are deducted for killing hostages even if it is accidental. So thats why semi-auto is used in urban combat situations.

2. Lets say you've just spotted an enemy and you both start shooting rounds off at one another. In the heat of the battle your gun jams leaving you defenseless against his attacks, however, if you had a pistol you could have easily pulled it out and finished him off. Having a secondary weapon on you at all times is, not only to your advantage, but your entire team would benefit from it.

I don't think that pistol is going to be firing 500fps though...not a chance. more like 400fps tops even if it is gas. I do like the gas pistols though...mine seems to be working for me quite well.