classic car cellulose paint

[rob07]

I am looking to buy some cellulose paint for my classic but am unsure which to choose. I have read that the cellulose available today is inferior to that available years ago. The paint people told me that they offer a better quality version and also a commercial grade but when asked for more details they were unspecific. Has any one experience of Jawal, HMG or Paint express or would they recommend another. I used to buy from morelli but they are way too expensive now.
Also how would an own brand primer compare to upol p88.