My regular brakes suck, i gotta double pump them so they bite.. I plan on upgrading to brembos..

 

Errrr, they're not like that because they're stock. If you need to pump them something is wrong with your braking system. You should have a mechanic look at it.

 

Common G35 issue.

Check your rear calipers and see if any of the slide pins are seized in place. This locks the caliper so it can't adjust as the pads wear. So you are double pumping to "take up the slack"

I've had this issue twice on my car. Both times were rear calipers. Had to replace the caliper ($50ish off rockauto.com) and my braking was MUCH better after fixing the mechanical issue. When in good working condition, the brakes on my G35x have a better feel and response than the brakes on my Benz C300 with sport brake package.

I've seen a lot of guys experience this issue, so def check your rear brakes.

 

I'll have to check it out.. They stop decent but when I double pump them I feel it bite really hard..

 

You have issues...^...factory brakes normally work good! Having to pump your pedal tells me you need to have a brake shop check them out. Past experience tells me you have a caliper failure that keeps the pads from making contact when pedal is pressed. Find an independent brake shop in your area, dealerships are just "Parts Swappers" until they find the cause! You don't need Brembos, they don't work any better than OE brakes for DD!
Gary