Breathing Easier...MAF and CAT Feedback

[guruerror]

I'm currently running my '05 with a K&N CIA, Gibson shortly headers, and a Flowmaster exhaust and am now considering replacing the stock Mass Air Flow sensor and going with a high-flow CAT or catless down-pipe to get the big boy breathing even easier.

I'm looking for input from folks on their results with either or both...(i.e., changes in throttle response, general performance, mpg, etc.)

Thanks in advance.