Would dumbell curls or other exercises be more effective?/QUOTE]
IMHO... No and yes and maybe....
Everybody`s arms (be it mentally or physically) will react somewhat differently to certains exercises and equipment, aka. barbell or dumbells. It comes down to you finding out what feels and works best for YOU !!!
Trial and error. Exploration. To boldly curl where no man has curled before.
The standing barbell curl is a standard mass builder pure and simple. No arguement there. It will never go out of style or fashion. Nothing fancy about it. It works. So are dumbells curls. So are preachers and incline curls. Nothing ventured/nothing gained. Follow me ? Exercise all your options until you find the magic bullet thats works best for you know who.
What is most important is the amount of effort you put into what it is you decide to do and always attempting to up the poundages.
As a foot note.......... the exercises you listed are all winners. The previous poster mentioned doing hammer curls and I agree. Hammer curls rock.
Pump on .....