CPP or Porterbult opinions air ride

[1968BURBAN]

Picked up a 68 GMC Suburban. Looking to lower with air ride and was looking for some opinions. Here is my thoughts.

Currently running 29" tires on 15" wheels. For the rear going to C-notch, change trailing arm crossmember, install upper shock mount bar, adjustable track bar, bags mounted to trailing arms, and maybe a 1 or 2" block, keeping stock trailing arms for now. (on budget for this year)

So... I can get the rear done with CPP stuff for quite a bit less than the Porterbuilt parts. Is there that much of a difference? I realize the PB notch looks like a better unit than the CPP but if I go CPP notch I was planning on reinforcing it some, body is off the frame right now so plenty of access to do what ever.

Thanks in advance for any opinions / advice