I thought about this for a minute because there were a couple of times in my restoration project where I was very angry but standing back and looking at it > 90% of the Moss parts were OK and without Moss Motors I would never got anywhere at all. A couple times I was saved by over night deliveries of A) an exhaust system and B) king pin set. All the parts I acquired for my restoration are listed on my MGB restoration page. http://www.greatvalleyhouse.com/MGB/mgbrestore.htm
My two most annoying issues were
1). a bad gasket in a new fuel pump that left me stranded on the road more than once and was extremely difficult to diagnose. Once I figured it out I replaced the gasket with the one from the 25 year old fuel pump that was replaced and all has been OK since. I wrote to Moss on April 9th 2000 and sent photos of the bad part. I never got an answer to the email that I still have on file. Part # 377-165 Fuel Pump Negative Ground. Invoice # 374105 Cost $89.95, Purchase Date 7/13/99. I still have the items in the image below.
Gasket
Supposed to fill cover.
2). Turn signal flasher. I bought three of these and they all failed within a month or two. Finally went to PEP Boys and got a generic product which has worked fine for the past six years. PS: IMPORTANT... You have to remove the glove box liner to find the flasher.
Quality is important. A bad part that wastes hours or days of a customers time should never be sold.
My first car: 1952 Hudson Hornet
First roadster: 1962 Austin Healy 3000 III
Still have: Computer free 1974 MGB
Previous Porsches since 1982: 924, 944, 944S, 97 Boxster, 03 Boxster, Now have 2008 Boxster
"If you wait, all that happens is that you get older." - Mario Andretti