Ahhhh! Helppp me! Maui in 24 hours!

Ok,

A friend and are going to Maui in the morning. Here is our equipment:

1D Mark II
20D

Canon 20-35mm f/2.8L
Zuiko 24mm f/2.8
Canon 70-200mm f/2.8L

QUESTION IS: I'm going whale watching, what should I rent. Please help me make my decision. I have to pick it up this afternoon.

1.4x Extender
or
2x Extender
or
Canon 300mm f/4L
or
Canon 100-400mm f/4.5-5.6L

I'm thinking the... Well I'm so torn. Please give me your experiences!

For whale watching a 100-400/4.5-5.6L on either your 20D or 1DmkII would be good. The 20-35/2.8L on your 1DmkII would be good for most other shooting.

Ditto the above post.

if you haven't been to these locations you might consider them:

Big Beach - South Kihei
Hana
Up Country

I could shoot Hana for a week alone starting with the Bamboo forest

I vote for the teleconverters and the 100-400. But if you have limited budget start with the TCs.