New models - what guarantee!

Does the various manufacturers have or show any respect after sales towards their customers?
I bought a Fleischmann 614 DMU diesel multiple unit from a Fleischmann registered retailer - right from the start, the unit emitted a loud grating sound while traversing over my layout. Fleischmann advised me to return the powered part of the unit to their address in the UK, cost of postage to be paid by me.
After four weeks, the unit was returned to my address in the same packaging I had used. No compliment slip or note was included to apologise for the inconvenience in having to send the unit back to Fleischmann or indeed as to cause of the noise emitted by the unit.
I soon found out as to why the absence of a note - the unit, to my horror was emitting the same irratating noise - in other words in plain english, nothing had been done and most probably not even checked over - the bubble wrap enclosing the unit, to me, looked very much like my own way of packing.
Prior to sending back the unit, Fleischmann stated that only one other model made a similar noise while in motion, and probably my unit would require some TLC and oiling of the gears. Certainly it looks like Fleischmann did not indulge my unit with lots of TLC and appropriate oil.
Fleischmann must have a strong hold of the H0/N gauges market and can afford to treat customers in such disgraceful manner.
I had a similar case with Bachmann over a guaranteed Class 158 making a not acceptable noise - the unit was returned in a identical manner, no repair being carried out.
Is this the way of manufacturers having no respect for their customers, to be accepted as normal for the 21st century. Slow