i dont really see a problem with going out with someone older. as long as they r cool with it- i was with a guy who was 2.5 yrs older and things between us worked out fine! i was (and still am) 17 and he just turned 20.. i think in some ways i was more mature than him..
it just all depends. even though there was almost 3 yrs between us- we got along so well. and i got along with his friends too..
it was distance in the end that killed us!
i say 2-5 years really aint bad.
problems may only occur when maybe the girl mite be younger and still at skool, and the guy's lifestyle is more free.. cuz they mite be at differnt points in their life...??
i knew a guy who dated a girl for 4 yrs until recently and she was 12 and he was 16 when they first started going out.. when he finished school and got into uni she was only in yr 11 and so they were at very differnt stages in their lives and they wanted different things... so they eventually roke up..
the whole skool vs a freer lifestyle more then usually clashes.. once ur outta skool i think its a lot easier.