andy78, have you test rode the bikes you have short-listed?
I ride Unicorn since 3 years (after upgrading from HH Splendor) and I like it.
In fact I decided to go for Unicorn after I rode a very old Unicorn bike.
Mind you the Unicorn you see now is slightly taller, and bulkier compared to the old version and to most, if not all, 150 cc bikes.
To me, although I like the bike, I advise you to test-ride it and then decide. Because it is taller and heavier, some average-built people may not feel comfortable with it. I am average built, and despite this I like it.
If you want to stick with the Unicorn, you may want to consider Honda Dazzler as well. I haven't got a chance to try it, but I believe it has same engine as Unicorn, but is slightly shorter, lighter and faster.
Just my thoughts!