To be fair I have not experienced great customer services from many main dealers over the years, and in all honesty I found my Alfa dealer to be one of the better ones - although I did see a lot of them (and this was 15 years ago). My only really negative experience with them the time it took to source a new a new crank for a 1.6 boxer engine which took almost 3 months and 1 was eventually found in India - I suppose that is the peril of buying a car with an engine which is about to become obsolete.
The best customer service I have experienced was my last Jaguar dealer, however you need to take out a second mortgage every visit.
If you constantly worry about something going wrong, you will inevitably find it and possibly wonder why no-one else can notice it but you. I gave up worrying years ago and since then have had many happy years of Ducati ownership which, apparrently, you can not have because they break down all the time and will leave you stranded - never happened to me in 8 years of ownership.
I am very glad I took the plunge again and bought another Alfa. Any 'worry' is far outweighed by the pleasure I get every time I sit behind the wheel and start the engine. It is the first time in years that I am truly enjoying my car. I appreciate that things may go wrong and I have budgeted accordingly for maintainance although I still have just over a year left on the original warranty.
Maybe I would feel differently if I had lots of trouble, but there isn't another car, in my budget, which I would rather own at the moment.