300 X 250 or 336 X 280?

Which one would be the most effective?
A medium rectangle 300 X 250 or a large rectangle 336 X 280?

Would it make a difference in eCPM or CPC?

 

medium rectangle 300 X 250 that works best for me.

 

I see, I will await more replys to see other people's opinion.

 

It all depends on the layout of your site......what works for me might not work for you...try one and if it doesn't work then try the other...even if it does work try the other to see if you can improve...

 

Thanks, I'll try that.

 

Many people say the 336x280 block is the best performing block available, placed above the fold. The 160x600 placed on the top left has always been the best performer for me, though.

 

Well, over a long period of time experimenting, the 336 wide format works best for me when integrated with my content inside a 340 wide table (2 pixels of padding on each side).

 

336 X 280 wins in most cases, including mine...

 

I prefer to use 332*280 ads