I'll never own one, because my local stores don't carry them, and I wouldn't buy something that expensive sight unseen. (not that I have the money to burn!) I own a Squier CV 60's P-bass and an American Std. While there are differences between the two, and the American is better all around, they both can nail any P-bass tone I want. I just can't see a Custom Shop sounding "better".
I understand that. Personally, I've never seen a CS or AV(except 70's) in a store. I've ordered online sight unseen. Keeping in mind that most online retailers return ship for free, and they even send the label and schedule UPS to your front door for a pickup. Its like having your own personal showroom at home.
The CS really does sound better. IF you took, a CV P, MIA P, AV P and CS P and blind tested them you would choose the best in reverse order starting with CS.
It cost more because it really is a better instrument. After holding and playing CS/AV bass you'll never wanna hold anything else in your hands.
I am not justifying the cost of these instruments but quality has a price. Not saying you can't have a quality CV or MIA etc.. but the AV and CS are more consistent in their quality.