Decisions Decisions !!!!!!!!!!

I have the chance to get an either or cpu. I have to buy a new cpu. I cannot decide between the BARTON 2500 0r the T-bred xp 2600. I have the Asus A7N8X Deluxe mobo with 1 gb 400mhz 3200 memory. I installed a 2600 for a friend and had god awful temps. like in the upper 60's. I installed a 2500 Barton and had mid to upper 30's temps. I will OC this chip possibly with watercooling. I read in TomsHardware the 2600 OC's well. I havnt seen anything on the 2500 though. SO....... does the 2500 Barton or the 2600 Tbred oc the best? I have to make a decision by noon today. My package will be shipped with a 2500 barton unless I change the order.
any comments or suggestions guys.............?