In my opinion.. the quality of your game play is directly related to the quality of your wireless router. Spend $40 on NetGear vs. $240 on high end LinkSys or other router and the experiences are going to be night and day.
Geography of the router and pc, what sort of electronic appliances, number of other pc's on the network, etc. also have a bearing on the performance.
My suggestion.. go to Best Buy, purchase the insurance when buying your router, give it a try at home and if it doesn't work for you, return the modem less the restocking fee and pick up some more Cat5 cable on your way out. ;)