There are a lot of discussions on the Samurai VS Tracker/Sidekick on here. I think the general answer is "What can you get that is affordable?"
Is it going to be trailered or street driven? Are you looking for more of an adventure build or rock buggy? 31" or 35" tires?
The Vitara/Sidekick/Tracker can be just as trail worthy as the SJ-413. There is just a bit more body to be smashed up.
The SJ has a lot more gearing options available with the transfer case, but if you don't need crawler gears and plan on doing an axle swap anyway, the Vitara is very easy to put a solid front axle under due to the true frame underneath it.