The bose system is just fine. Throw a sub in the trunk and call it a day. Its pointless to have a bose system and swap the door speakers without going with an aftermarket amp. The door speakers were made for that car. They have plenty of mid bass, depending on the quality of your cds. I have been an installer for 8yrs now working with jl audio, alpine, focal, ads,eclipse, marantz, etc. and I haven't even thought of changing my doors out. If you wanna go big and do it the right way without going to best buy and throwing some cheap pioneers in the door plan on spending a few thousand. you spend 30K plus on a car why go cheap. Go with jl 500/5 channel , focal k2s for your seperates and maybe a w6 in the trunk. Basically if you going start changing things out do it right.