I make handmade kitchens and will often fit rigid built off the shelf
kitchens for friends. All of the companies mentioned have there +ve's
and -ve's. Magnets offer reasonable quality kitchens at a price which
can be competative if you buy through an account holder. Howdens (my
prefered route) offer a great service to the trade and at great prices
(I have just fitted a kitchen in my local hall 4.2mx 3.5m for £3.2k
including a double sink, handwashing sink, oven, hob, extractor and
splashback- appliances sourced elsewhere and I am walking away with a
nice amount of money too). You will never get superb quality from a pre
manufactured kitchen, but installed properly with all edges treated for
water ingress, you'll get a kitchen that will easily last 15 years. My
handmade kitchens would last a lifetime, but cost 5 times more. And
people often want a change every 10 years too.

What does anoy me is hearing stories of folks buying moben kitchens and
the likes and paying the same sort of money that would get them a
bespoke handmade kitchen with no MDF or chipboard. A handmade kitchen
will typically cost £16k inc granite worktops.

As for units only having thin backs, again you get what you pay for,
but there is no need for a strong back other than piece of mind. It
doesnt add to the rigidity of the units. These premanufactured units
are well designed to give a combination of strength versus weight and
material cost.

One good thing about magnet and howdens is there stock level... where
else could you walk out with a kitchen the same day as ordering it.
MFI, Homebase, B&Q etc- unless buying their budget range- will take
typically 6 weeks to get it to you, and then if there are things
missing you need to wait another 6 weeks.

Hoping this is of help
Calum Sabey
NewArk Traditional Kitchens 01556 690544