125x125 or 160x90 that is here the question

Replace 125x125 buttons with AdLinks 160x90?

[jetteroheller]

I place my ads usual below the 2 menu columns

Below the left chapter menu a 120x240.
Depending how much space is below the right page menu,
I place

120x240
125x125
160x90 since yesterday
nothing

Now I just thought to replace all 125x125 with 60x90.

What's Your oppinion about the performance?

[jetteroheller]

To test it intensive, I have now 1187 AdLinks 90x160 distributed.

Some of them replace 125x125, at some others was enough place above a 120x240