Our insurance is up for renewal too.
I've got to be honest, I tried all of these 'forum discounts' - A-Plan, AIB, Adrian Flux.
After going all retro and spending 20mins on the phone going through all of your details (had forgotten how bloody laborious that is!) None of them were much different to the comparison websites.
You can probably get a better deal finding a good option on the 'comparewhoever.com' sites and use Quidco to get cach back from a direct quote/purchase.
Just my experience....