hey lou, basically exact same engine as the zr diesel so pretty much similar mpg performance ect, the 110 and 120 petrols will get about 40-45mpg on a motorway run sitting at about the limit, never worked out what it is day to day driving though.
just need to factor in a: initial cost of a diesel over a petrol, b: cost of diesel compared with petrol: c: obvios getting a petrol make sure stick ?400 by incase of hgf
common problems, well fairly reliable cars both petrol and diesel, think the MAF can play up on diesel, aain hgf on petrol, door handles coming loose at the backing to the door, n other stuff nothing majorly different to any zr faults
basically if you love your zr then youll LOVE the zs, feels a bit better to drive n put together wee bit better
any questyons just ask away