Sandisk Extreme Pro CF Card

Right now,I am using the Sandisk Extreme 4(45 MB) CF Card with my Canon 7d DLSR camera and I love shooting sports.My question is,would it be worth upgrading the Sandisk Extreme Pro(90 MB?/Shall there be a noticable improvement if I upgraded to the Sandisk Extreme Pro from the Extreme 4?
Thanks.

Here's a post in another forum where I tested several cards. Here are the conclusions I reached:

So, before you splash out on a 60 or 90 MB/s card ask yourself some questions -

* Do I often fill my camera's buffer?
* Do I ever fail to get a shot because I'm waiting for the 'Busy' light to go off?
* Do I have a high-speed card reader (Firewire 800, Expresscard or eSATA - not USB2)?

If the answer to any of those questions is 'Yes' then a high-speed card may be for you. If the answers are all 'No' then you'd probably be wasting your money.