Linear Puncher Rubber Bands

Can anybody give me a link to long lasting and consistent elasticity rubber bands. I need them for my linear puncher. I also wanted to ask, does latex free rubber bands work better?

Many teams use these - http://www.amazon.com/Alliance-Sterling-Rubber-Band-Approximately/dp/B008X0A0Q8/ref=pd_sim_229_1?ie=UTF8&refRID=03Z8E94K3R2SHSX5VZS4

These are good ones too but the stretch characteristics are different than rubber ones.

http://www.amazon.com/Alliance-Non-Latex-Rubber-Bands-Allergy-Reactions/dp/B0017D5X9C/ref=pd_sim_229_1?ie=UTF8&dpID=51GeVP0HaQL&dpSrc=sims&preST=AC_UL160_SR160%2C160&refRID=0QRYJW82C9ECG9Z738JJ