Reliabuilt would be one. But to be fair, nearly every door distributor offers simple steel entry doors at a very low price point. I can purchase a simple entry door from my distributor for slightly under 190.00 and its not bad.
I cant speak for Peter and Sam's situation but for me I think these issues come in a wave when the distributor/manufacturers get over extended and things get out of spec. As has been stated, at least the distributors I have been to, these doors are not milled on anything close to a CNC. They are mortised on a door station like this:
https://www.youtube.com/watch?v=fsJ2iDgc3H4 If anything on that machine gets out of spec several hundred doors can go out before it ever gets back to the distributor.
Interior doors are hung even more crudely than that.
There are more automated setups but I have never seen one.
Its definitely true that this has to get back to the vendor/supplier but unfortunately I think as Sam stated, all too often you just have to do your best to get it done and even though you may pass along some harsh words to the supplier the next time you see them I will bet it never makes it very far up the chain.
In my last nightmare I received a phone call from the owner of the door distributor who actually works on the shop floor every day and he basically told me that the garbage he is being sent from south america is very difficult to deal with but, just as me, he has to keep production moving.
Ive long wondered when we will hit the tipping point and people will start to get fed up but even in these scenario's the pain often times never makes it to the homeowner because the contractor is dealing with all the headaches and the bottom line is the sale is still made.
Long been brewing, who knows where it will head.