Noticed that Del Po was using a K-Factor stick vs. Tipsarevic. So I sent a tweet to Wilson tennis asking why Del-Po was using the K-Factor and Wilson replied: http://twitter.com/#!/WilsonTennis/status/41984331517923328 "We are glad he is back out competing and we will have something new from JM and us later this year. Stay tuned!" Interesting. Wonder why he switched?