Oh man, I don't drive my wife's car (the G35S) frequently, but when I do, I'm constantly amazed at how poor the brakes are. I mean they stop the car, but the feel really is bad (mushy pedal with lots of travel compared to what I'm used to).

It looks like the upgrade options are (from cheapest to most expensive):

1. upgrade the lines, pads and fluid
2. upgrade the lines, pads, fluid and rotors
3. Akebono upgrade kit (which will require spacers AND/OR bigger wheels
4. other BBK kit (new wheels too likely)

I'm leaning toward a line/fluid/pad change to see if that helps and potentially the Akebono upgrade (it's quite reasonable IMO, but I'm not excited about potentially needing new wheels (just bought new tires a couple months ago).

Has anyone just done a line/fluid/pad change and seen a positive impact in the pedal feel and brake performance? I know on my Evo, the pad I use has quite a bit of difference in how the brakes perform, but my pedal is always firm.

The S brakes aren't that bad.....
When was the least time the brake fluid was flushed?
I would start there with some SS lines.

In my personal experience, the mushy pedal is a result of the lines more than anything.

A flush (depending on your mileage), upgrade to SS lines and possibly new pads like you suggested will do a world of improvement, especially in the pedal feel. An upgrade to the Akebonos will result in pedal feel, but that's more a result of the SS lines more than the larger rotors/calipers.

If the pads still have lots of wear left I would go with a fluid flush to make sure you have all air removed which will give you a mushy pedal. Stainless lines will help but you should not have a mushy pedal with stock lines either. If going with stainless make sure you are getting high quality stainless lines with proper fittings instead of cheap stainless which often are nothing more than a sheath over cheap conventional lines. In those cases you will sometimes have the benefit of the stainless with early failure due to the braid working on the conventional hose material.

You sure the wife hasn't glazed the stock rotors over?

thanks guys. Maybe I'm spoiled by the Evo's brakes, but I don't remember her G35 coupe (brembos) feeling as poor as these brakes.

The fluid's never been flushed, but the car isn't very old (16 months?), never been driven hard or anything.

If the rotors (technically the pad) were glazed, it would feel wooden, not squishy.

I think I'm going to go with the less expensive route, pads, lines and good fluid and see where that takes me.