Just had my renewal notice, up a fair bit on last year and now north of £500, which is More Than I want to pay (See what I did there?!.

Quick trawl of a price comparison, and the SAME INSURER comes out £300 cheaper and still weren't cheapest!

Needless to say, they'll not getting my business any more.

Why do insurers (and pretty well all utility companies) think it's OK to shaft loyalty? Do they have company policies to treat us all like mugs?

I am afraid is is just they way they function!
They know some people will not bother to keep looking around and therefore they see renewal business as more profitable than new business.
I renewed 2 car policies this week for an Audi and Saab and saved £80 by moving away from the previous insurer to the new one.

Indeed, I insured my Grande Punto yesterday with an identical policy from the same ultimate insurer (ABC Insurance) for almost £100 less by switching names on the top of the insurance certificate.

When I rang to tell the present insurers that I would not be renewing with them, their comment when told the reason was to ask if they could re-quote to give a lower premium.

I refused, as they should not have tried to rip me off over the renewal.

In contrast, the insurance I take out for the coupe is not price dependent.

It is all about getting the specialised cover I need, (agreed value, salvage option, UK and European breakdown cover with full repatriation) so I am unlikely to switch providers for the coupe come 1st April at the end of the present contract.

If this is on a Fiat Coupe and it's not too late give me a call

Regards
Sarah