17x9 +45 is a very nice fitment. i would go with that.
it also sticks out more than the second set.
a little modification would be required to fit e.g rolled guards, bumper tab relocated, neg...
This is the process I used to remove my Toda Headers and re-install the stock headers.
The same process can be used to remove stock headers and install aftermarket headers.
No probs. It's an annoying problem to have especially when you are in the middle of traffic or at the lights. Everyone just thinks you want to drag them.
how hard are you slamming it? the s2000 bonnet is aluminium and is pretty light. i find it requires to be dropped from about chest height to close properly.
it's likely due to your idle air control valve (iacv) being dirty. you can replace the part or just pull it out and clean it yourself. the iacv is attached to the bottom of your throttle body.
you can also pull the cel code by using the 'paperclip' method. takes about 5 mins. instructions here: http://www.k-series.com/tech_document.php?id=37
then just refer to the dtc table to see which...