Herefishy,
As Jim pointed out, it's the tippet that determines how much 'pressure' you can put on, and thus how 'quickly' you can land, a fish (given YOUR skill level, of course). Rod weight is irreleveant given equal tippet strengths and that you can BREAK the tippet with the rod.
Your three weight is fine for places like the San Juan or similar streams and rivers.
With the small flies and light tippets used there, I doubt you'd feel any difference in how you 'fight' a fish between a 3 and a 5. In many ways, the lighter rod is superior in such circumstances, as it flexes more easily to protect the lighter tippets.
Lots of the guides up there are going to 9' 3 wts. for just that reason.
If you are going to be throwing #2 streamers on 0X tippets to big browns from a drift boat, then you may want a bit heavier rod.
The 'key' is making sure that the tippet is the weakest link, NOT your rod.
Good Luck!
Buddy
It Just Doesn't Matter....