The 2.2 is a cracking little engine.
The only thing I would warn against is the out-of-the-factory
town driving experience is not the best.
You need a lot of clutch dipping and throttle blipping
to keep the car from Kangarooing in heavy stop-start traffic.
The only fix for this is from AutoDelta, after which the
2.2 is a dream intown.
Cruising is great eitherway. The Brera eats miles
and is very very comfortable on long sprints.
I'm sure a DERVist will be along shortly to
inform you about
the merits of the diesel.
I will say this, If you do a lot of town driving,
and can't get an AutoDelta remap for the 2.2: Get the DERV.
Otherwise take the lightweight 2.2.