I agree with you! When you jack your car or take it on stand you have to think about the weight repartition. If you use 2 stands for the front, you can pretty much divide the weight by 2 since the 2 back wheels are still on the ground. In plus 4,500 lbs : 2 = 2.250 lbs and if you use 2 floor jack that will be 2.250 : 2 = 1.125 lbs on each. It's find! But always apply the rule of double security. That mean when you need a specific level, choose the one who can support the double! :TU:350 lbs of speakers in yer junk?
But your not picking up the whole car so 2 ton is fine. I would make sure you get a low (or sport car) jack. That way if you ever lower your car you can jack it up without needing 2x10's.
I recommend buying a jack AND ramps, as ramps are safer and easier to use for most routine maintenence.