from what i remember with my mates getting their p1s, i think the engines were prone to letting go about the 40k mile mark, although may have been down to folk fitting exhaust without a remap.... if you can get a mint condition p1 it would def be worth buying, i would have 1 in a flash...if it is standard and you want to make sure it is safe then why not buy it and pick up another ecu(eg apexi) and get andy f to map it, that way you got the car you want and the peace of mind of a safe map??
scott