Their responses come following the launch of the Fleet News Fair Dealer campaign last week.
Fleet News is campaigning to improve dealer service levels for fleets and company car drivers following a series of damning reports about standards.
The Fair Dealer campaign is highlighting best practice and condemning unacceptable service to push for a better deal from dealers.
Fleet operators can make their own voice heard by registering whether dealers are a source of pleasure or pain by clicking on the Fair Dealer button on the homepage.
Among the fleet decision-makers who have already made their voices heard is Mick Jackson, fleet manager for BEW Electrical Distributors, which has a fleet of 65 vehicles, including 25 light commercial vehicles. His summary of the dealer experience is damning. He said: 'I believe main dealers are a licence to print money. Their labour rates seem to rocket as soon as they find out it is a company car in for servicing.
'The bill can be different even from the agreed figure when the car is booked in by myself via the telephone.
'I believe they are aware that the company representative who brought the car in is paying for it on his credit card, knowing he will claim his expenditure back, unquestioned by the relative department of the company he works for.
'They always seem to be full of excuses as to why they have not made a mistake. I am sure they wrote the book A Million and One Excuses for the Motor Trade.'
Like many fleet decision-makers, warranty claims were a major bugbear and he is having an ongoing row about a jack and wheel brace that went missing following a routine service.
His overall complaints cover a wide range of manufacturers, including Nissan, Saab and Mercedes-Benz.
He said: 'One car was left in the dealership's car pound earlier this year for eight weeks, while I wrongly assumed and was wrongly informed that it was in the workshop undercover and being fixed. They wouldn't even give me a courtesy car.'
He added: 'The day it was ready, I went to collect it and found the windscreen broken, not just a small crack, but 18 inches long in the middle of the screen starting near the wiper spindle. Another trip home on the bus for me and not so much as a 'sorry for the inconvenience, sir'.
'I think I have had more than my fair share of bad deals with main dealers and I hope and pray that others have had better.'
Ian Smith, group accountant for CPiO, has created his own general list of goods and bads by manufacturer. Unfortunately, he feels most fall into the bad category.
He said: 'At a Vauxhall dealer, I was charged for a replacement cam cover gasket when it was clear that the retaining bolts had never been removed.
'At a Peugeot dealer, I was told there was nothing wrong with a poorly running and vibrating vehicle more than once. Less than 20 miles later, it gave up completely with a shattered flywheel and took the gearbox with it.'
However, he introduced a bold plan with some dealers to get the service he wanted.
'A Mercedes-Benz dealer refused to accept that there was a gearbox fault on a brand new C-class. The gearbox seized while it was being delivered back to us. The good thing was that they only had an S320 available as a courtesy car and we refused to give it back until our car was returned with a new gearbox.
'At a Volkswagen dealer a cambelt replaced at a 40,000-mile service broke a week later. The car was off the road for 12 weeks waiting for parts and then the dealer chased the service bill while the car was still off the road.
'Again, we held on to the loan car once a decent one became available to put pressure on the dealer. Still, it took three years to get a credit note from the dealer for the cambelt replacement.' He added: 'I am not really impressed overall with dealers. Audi seems to be the best, but inflexible. Rover dealers offer reasonable service but are very expensive.'
John Clarke, of fleet services south for Telewest, said he now focused on using independent dealers.
He said: 'My experience of servicing arrangements has taught me never to use dealerships wherever possible. Too many dealerships view fleet vehicles as an open cheque driving into the premises.
'Fleet vehicles are welcomed by most dealerships but only to go at the back of the servicing queue because they know most company drivers will be supplied with a hired vehicle so really there is no need for them to break into a sweat and get the vehicle returned as quickly as possible. Add to this the fact they will get paid the full amount for what they say the vehicles actually require and you have all the ingredients for financial ruin.
'Non-franchised garages in the main are completely different, even more so if they rely on a large number of company vehicles from a single customer. In my experience, they bend over backwards to please the client by reducing downtime and still provide free-of-charge courtesy vehicles.
'There are plenty of very good non-franchised garages out there and employees with fleet responsibilities need to go out and find them. It is not too difficult a task – just ask the motoring organisations who use them to supplement their own network.'