yammyfan: I don`t know if I`ve not read the post fully, but is it a Coupe or Roadster that you have ? If it`s a Coupe, it will be 265bhp, and
should feel fast enough for the road, at least, maybe ?
I`ve had loads of cars, and bikes (including an R1, a few `blades, Gixers, ZX`s.........all sorts), and IMHO, especially riding as you will at 21, you`ll never get the same rush from any car as you do a bike..............so; in view of that, I`d stick to the 3.0 and save on the insurance/running costs, etc...
I`ve never owned, or driven, a Z4M, but I have owned an E46 M3, and although it WAS quicker than the 3.0, it didn`t feel appreciably-so, in most real-world driving situations, until you start to head into licence-losing territory, and I don`t know if the extra performance will still leave you feeling a bit wanting in the long run (again compared to the bike) ?
Do you drive with the Sport button on, or off, by the way. I`ve found that the Sport button makes a major difference in every day driving, as the engine is so much more responsive. To me it`s just how it should be all the time, and if I`m honest, I don`t really see the need for the Sport button at all.........it should be running permanently on this map in any case !
Just my tuppeny`s worth mate, but it may just be a case of accepting the Z4 for it`s strengths, AND it`s weaknesses, as the adrenaline`s never going to flow the same as it does with a bike. Good luck with your choice anyway, and all power to you for being able to afford these toys, and their associated costs at your age.......
Nice one ! 8)