Have a talk to the Sales manager at North Oxford Garage 'NOG' Phil. He'll put you in touch with the BMW specialist insurers (a department within Devvit who also do Honda and other make specific cover).
I ride a 1200GS and pay £136.pa. My self and my other half who rides an R100GS both find them the cheapest option. Well worth getting a quote
Something else I would seriously advise:
Reading that you are returning to bikes after a fairly long absence I would suggest that you get some skills training before heading off on your daily commute, especially if that commute involves city centre/ring road traffic.
A call to your local Motorcycle training centre to book a 'back to biking' day on one of their bikes could make a really big difference to the early experience of your new bike and your health.
I see your in the Oxford area. If you can't find anyone who does this type of day then call the 'Bike School' in Devizes 01380 726966 (only about 50 miles from you) and they will happily get you going. (yes I work there, and I used to get my 1200 serviced at NOG)
Alternatively make contact with your local RoSPA/IAM (through in my experience of three advanced tests over the last twenty years, RoSPA is by far the better) group and get them to take you out for an advisory ride.
Finally: If you haven't ridden seriously for the last 3 years or so, do your self a favour and get a bike with ABS fitted. You won't notice it till you need it and even then you might not realise it has just saved your bacon. Besides most BM's will have it fitted anyway.
Good luck with your new toy when you get it, and ignore most of the negative stuff you read on here. It's only one person in a thousand or so that have these sort of issues. They really are quite rare and the bikes are great

, my 1200 has done 55000 with on problems.
Val.
PS: when your fingers and knees get cold send me a PM and I'll sort you out with Muffs and a Gaucho.