I have made MANY out of the way trips to get a credit. My rule, however, is that a coaster has to be considered an "adult" coaster for me to go out my way to ride it. In other words, I will not go out of my way to get to a park that only has a kiddie coaster, but I will go out of my way to go to a park that has an adult coaster and then ride the kiddie coaster while I am there for the credit. As far as what constitutes an adult coaster, I base that on the size of the coaster and the height requirements for the coaster. I use my own personal discretion, and that works for me. That doesn't mean that you should follow the same guidelines.
As far as counting clones is concerned, I count every coaster individually, even if it is a clone. Every park setting provides a unique experience for every ride, and identical twins are in fact two different people, so I count coaster clones as two separate and unique rides. I will not count a ride that has been moved to another park if I already rode it in it's original location. And, I do not count coasters that have gotten new, different trains or that have had slight modifications made to the ride experiences. Once again, just my way of doing things.
In my opinion, counting coasters is really a personal thing. It should not be a contest, and it should not be a cause for argument among coaster enthusiasts. Do it however you want to. Whatever makes you happy. Just make sure that you are (Like Robb says!) HAVING FUN!
- Jason