All depends how you drive it.
If you're going to thrash it about on short journeys, expect something in the region of mid 30's. But then when you need economy out of if, I can see mine creep up to 60 and beyond, on long motor way journeys. It all depends where you sit your cruise control at.
Town driving, if i'm not in a rush I'll expect to kick about 45-50 out of it.
My sister has the 1.2 TSi, and to be honest, I've never seen her get anywhere near the figures which everyone raves on about. She was down to as little as 24 the other day, but like I said before its all on the size of your journeys and how you're driving. I think she averages about 35.
If i was you, you're going to get better economy out of the 2.0TDI engine, and a **** tonne more of torque, which is always fun. Yeah the price of diesel is "slightly" higher, but the range you'll get out of a tank is that much more, so I never really understand why people bring that into the equation.
As far as the DPF filters go, I've had my light pop up on my dash board once, I was driving the thing like a tit, and booting the **** out of it, start stop style. I just took it out for a spin doing what it says in the manual and it dropped off, never has it been a
problem. the 2.0TDI CR engine was built in mind of the DPF filter, whereas its predecessor 1.9TDI PD engine wasn't so much, which is why they had a lot more problems.