The 7mm. is definately, not too much gun for whitetails. The fact remains that many hunters use the 7mm to harvest deer and even larger game. Some people use the 300 win mag to hunt deer, and many claim that that isn't too large either. The 7mm is a great cartridge for deer. Very flat shooting and hard hitting. Anything from .243 - .54 caliber muzzleloaders have been used totake deer. You most certainly dont "NEED" a 7mm to kill deer...but a good 7mm will open up your shot opprotunities to a moreextended range than lets say a 30-30. With a 30-30 ,150-180 yard shots are possible, with a good 7mm...you can reach out and touch someone with that.....so its up to you and the way you want to hunt with it. the 7mm is neither too much or too little of gun...because that all depends on how you are applying it.
GOOD LUCK HUNTIN