Yeah, there are at least a couple different systems that go by the name White Crane, and they are completely different, are not even related. The Southern Fukienese white crane may be an ancestor of Wing Chun, and it definitely has some similarities in how it looks. the Tibetan White Crane, which is what I do, has a completely separate history, looks very different, is not related to the Fukienese style at all, and simply has the same name by coincidence only. There is no connection between the two. What happens is that different people in different locations happen to find some kind of inspiration in the same animal, they develop a system based on that inspiration, and they call it by the animal's name. But this happens independently of each other, and the "crane aspects" that one method focuses on may be entirely different from the "crane aspects" that the other group focuses on. This is why they can look so differently in terms of their fundamental techniques and in how they approach training and fighting. Each group is looking at the crane in a different way, and the way the crane principles are expressed can be entirely different. And yet they are both Crane, just in their own ways.
The Fukienese method is probably more widespread than the Tibetan, and from what I've seen there are several sub-methods within the Fukienese system. Not so with the Tibetan system, tho the Tibetan system has a couple of sister systems that developed from the original system, they all simply branched and went in their own directions and became separate and distinct, yet still related. Hop Gar and Lama Pai would be the sister systems of the Tibetan White Crane.
There are very few teachers of Tibetan White Crane, and I think most of those who are out there are not very good. I would be surprised if you found one in your area, but I guess anything is possible. I do know there are some teachers in South America who are connected to one of the teachers in Hong Kong. I don't remember where they are tho...maybe Venezuela? I don't know if any of those folks might have made it into Mexico, or anyone connected to the teachers in the US or Canada, or elsewhere. Like what Sean says, I think it depends more on you as an individual, and what makes sense to you as an approach to training. There can be some physical issues that might limit you from one system or another, but I would say those limiting factors are your own personal limitations and not simply because of your build or size in the general sense. Taking a look at what is available to you is the best approach to looking at your options. Trying to determine what might be best for you on a hypothetical level is kinda pointless if that method is simply not available to you.