Well, that's a novel way of getting into bikes. Not heard that one before.
My own guess is that you are going to be disappointed with it. Running in my Daytona at low revs was about the most frustrating thing I ever did. But at least I knew that in a couple of weeks I could let her fly.
For a little extra effort you can buy yourself a snappy little learner like the Aprillia 125, which will blow the socks off you. You can then trade her up when you are ready. That way you will have more fun - and still been quids in.
I don't buy your logic. Your decision sounds more like a hormonal than a rational one (especially in the light of your insurance premium). I guess you are caught up with the idea of big bikes rather than the reality of them - but then how could it be otherwise!

Yuh pays yer money...
But like everyone else, I'm intrigued to hear what your experience of it is. If you do go for it, You've gotta write it up for us.
BTW which part of Blighty do you hail from?
Whatever you choose to do, ride safe and take care