the 3.4 is faster than the 3.6, not sure how becuase the 3.6 has 20bhp more . . . . but it is.
the 2 and the 4 handle completly different, its all down to personal taste, both are as good as each other.
make sure he gets a warranty, from porsche NOT from RAC or a third party, this will give you peace of mind that the car will not give any expensive problems down the line, like RMS.
there is a small issue with RMS (rear main seal) basically a small number (less than 3% i think) have had this problem, if the car is covered by the porsche warranty then they will fix this, or hell, any other thing that is wrong, under the warranty (friend of mine had a engine replacment on a 9 year old 993, 20 grand new, cost him nothing)
cabriolets dont handle the same and are slower, unless you dad owns a string of hair salons, avoid a cab.
tiptronic was first used in mass produced road cars by porsche, dont be fooled by this, tips are harder to sell and cost less to buy "used" they also dont have flippers but use buttons on the steering wheel instead, its not as good as the one on M3CSL with the flippers, Tip's are also slower than manuals.
make sure the car has the upgraded sound system, this was somthing like a 2 grand option from new but is well worth it, the std one is pants.
GT2 are the daddy, but please note there are several versions, RC, CS, compfort, RS evo, RSR, SCRS etc etc etc, the RS and CS are the only ones worth buying, the evo and rsr etc are silly money, and not really used on the roads.
same with the GT3, RS and CS will hold their value a lot more than the compfort edidtion.
there is a nice C4 on pistonheads for sale that was the feature car in Evo back in feb, was originally bought by barry venison (footballer) so the spec is high, I know the owner Matt, hes just sold his TVR and bought a GT3CS so selling the C4 since there is no need for 2 911's, youd find a lot worse then this for 5 grand more.
http://www.pistonheads.co.uk/sales/75076.htm
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