Chase Perfectcard and Chase Marathon Mastercard

[Credit King]

I have both of the above cards. I mainly use Chase Perfectcard for all gas (other than Marathon) and other purchases (where they don't take AMEX). However, when I buy Marathon gas (when competitive) I use the Chase Marathon card (7-8 times a year). It pays 5% on ALL Marathon purchases including auto repairs, etc. It just so happens my mechanic is a Marathon dealer. I use him about five times a year, and get the 5% on auto repairs.

The Chase Perfect card pays 3% on all gas and 1% on everything else.

The question is: Is it worth maintaining the Marathon card for the purchases listed above, or should I consolidate it into the Perfect card?

P.S. My primary card is AMEX cashback (green).

[hh]

Why not keep both?