It must be late 2010 production date - the 2nd face lifting (new TI seats, black alloy on console etc).
Looks nice, proper Alfa paint. It is TI, so you have bigger/more effective Brembo brake disks/callipers, and bit stiffer/lower suspension (with 19" rims especially stiffer feel). Very nice seats with leather outside, alcantara inside and red details - I would dream about such.
If you are OK with Diesel and/or do more than 10kmiles per year, this engine is wise choice.
Personally I changed my 1.9JTDM after 6 years to 1.75TBI, and although I'm happy with how car runs, I feel I'm too often visiting petrol station (I do ~600 miles/month, mainly short distances) - TBI uses 60-80% more fuel than JTDM.
Late 159's and 2.0JTDms engine configuration are rather problem free - e.g. use F40 gearbox (I never heard complaint on this one).
Of course buying any used car there is always some risk - depends how the car was maintained(oil changes more often than user manual says), if user let the engine warm before pressing pedal to metal etc. If you like the car, do careful inspection, check service history, and if all is fine make decision.