Newbie Question: Is factory air suspension easier/cheaper to swap to aftermarket?

Hey everyone, I'm looking at some LS 400 to start out with and I know they come with the option for factory air suspension.  My first mod to the car would be a good air suspension set up and I know just throwing on a controller and driving around low will blow the stock bags in no time.  So I was wondering do the cars with factory air suspension have any advantage over the non air suspension ones when swapping to a full aftermarket set up?

Things I have learned through my searches are:
Have add a tank anyway as stock only uses a small compressor
Stock adjustments are slow
stock bags blow easily driving around "aired out"

Things I'm wondering about:
Does the chassis or other suspension parts have any type of special modifications already done from OEM to accommodate air suspension?
Can factory lines and/or level sensors we incorporated into aftermarket set up for easy of install and/or lower cost?
Can the factory system be "slowly" upgraded piece by piece to an aftermarket set up?

Thanks in advance.

Things You're wondering about:
1. NO
2. NO
3. NO

Okay, thanks for the info Rodneyc77!

So really the only benefits is I get use to what air ride will kinda feel like.
Would it be recommended to follow the OEM air line layout as much as possible as long as the new air line clears?

i think the bags should last for a decently long time, as long as you dont drive too low, my buddys LS430 drives pretty low and he dosent have any issues at all with his bags, to my knowledge. how low where you thinking of going??