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Which is better? What are the pros and cons of each?

Since you're posting this in a turtle forum, I'll guess that your poll stats will be leaning a little towards the first option.

I wish I could answer your question from both perspectives, of a turtle and a tortoise owner, but I only own a red ear slider so I'll tell you why I chose a turtle over a tortoise. First of all, I feel in love with red ear sliders. From the research I made, it seemed that aquatic turtles are easier to maintain than tortoises and also more entertaining to watch. I hear that you have to change the substrate in a tortoise enclosure quite often and throw it away, as opposed to water that costs literally nothing. Also tortoises spend quite a lot of time buried in the soil and only come out occasionally and to eat. The fact that I went from having fish to aquatic turtles also made my decision a little easier.

Note: My knowledge about tortoises is a little limited, basing it only on the few things I've read on this forum or hear about from friends, so if any of my facts are not 100% correct please feel free to set things right.

I only have a RES at the moment, though I do hope to get a tortoise or other land turtle at some point.

I vote land turtle/tortoise because they are just awesome. They can live outside (as long as your temps aren't crazy) and you feed them and they can just wander outside in a fenced in yard. Their setup can be a little elaborate (you want a screen of some type over the top to keep out predators) but once it's built, it's pretty much done.

On the other hand, RES and other aquatic turtles are basically big fish. My biggest issue with them is that they require a giant tank but it's almost always empty (fish get eaten, additional turtles mean additional gallonage, etc). So I think it's definitely all about what type of pet do you want, a big fish or a lazy, hard-shelled dog?