The 1st gen owners will say 1st, the 2nd gen owner will say say the 2nd. Which ever you pick, you'll be happy with it. I know the 1st is a beast of a motor, but the 2nd gen isn't no slouch either! You can get a 1st gen for slightly cheaper than a 2nd gen (in most cases) so if you're worried about money for modding, go for the 1st gen. If not, pick which ever one you like better visually cause unless you're out drag racing or taking it to the track, it's not going to be a dramatic difference.
BTW, I'll have both gen 1 and gen 2 for sale shortly. Where are you located?