The XTreme-G are VERY good drivers. I have got high performance from them, but on one of my simulators i have a crashing issue. I just load WHQL's when using that sim, and run the XG Drivers when using everything else.
It really depends on the simulation/game, and the system specs, and what card you are using. Different cards react differently.
BTW, there are NO pointless questions. People who ask questions, ask because they don't know something and need to know. Nobody knows everything, and it's the people who realize that that actually learn something. Those who think they know everything usually don't know jack.
aTi, your question was just as valid as anyone else's here, and you can ask as many questions as you want.