I have a 3.2 Sportback. I am with Admiral at the moment. Renewal came though over £200 more expensive than doing a fresh quote on the web with them, but they matched it, fortunately for them. Admiral and Elephant are the same companies. Privilege was cheaper though (part of Direct line) as they guarantee to match your renewal subject to some requirements.
Personally, I go with a company whose ability to manage claims effectively comes recommended from others. They might be a bit more expensive than the cheapest for me, but I have heard from colleagues (also an insurance broker friend) who have had dire experiences with customer service / claims handling etc from other insurers just when they need them the most - especially Tesco.
General tips from my experience - make sure that your expected mileage is reasonably accurate - it does reduce the premium if you are doing lower mileages. Also, add your wife, girlfriend, female cat or whatever as an additional driver as it always seems to reduce my premium (you don't have to tell them!) And if you or additional driver drive other cars, then say so as this seems to help too. Finally, never pay monthly unless it is free (never seems to be!) as it is always cheaper to pay on credit card as interest rates for this are normally very high.
Rob