Definitely agree - get a Land Camera if you want to get into instant film. The 250s are great, but so are the 100 series, so that can expand your options. My 100 is a rangefinder and has some controls for aperture. I don't know much about the 300 and 400 models. Regardless, the advantage of this variety of Land Camera is the peel-apart film that Fuji makes is very good and still in production. Polariod film - which is now all expired - is hard to come by and it's expensive when you do find it and you can't always be sure it's been stored properly. The only other option for film for 600 or SX-70 cameras is Impossible Project, but those packs will run you about $23-26 for a pack of 8 shots. That's $3 per shot. And the emulsion is great if you hit it right, but it's a very fickle thing at the moment that they are still trying to get right.
The Fuji 100C (yes, that's 100 ISO color) is $9 a pack (10 shots) on Amazon, so it's still more expensive than 35mm or 120 film, but not nearly as costly as Impossible Project. And like I said, it's a really really nice emulsions. I'm really pleased with it. There was a 3000B (high speed black and white) that is just beautiful, but it's been discontinued. I got myself a stash while I could and a few retailers still have some, so I get a pack here and there when I can. But hopefully the color will stay.
And I have hope that it will, because the Fuji Instax series of cameras and film have been very successful. The Instax cameras might be an option, too. They're not that cheap - the mini (size of a business card) runs close to $100 and the wide (about a 2x3 image...sorry, I don't have the metric numbers handy) is something like $65-75. And they're much more automated, which can be good when you don't feel like thinking about it, but it can also be frustrating if you are used to more control. And you can sort of turn off the auto flash, but if the camera thinks it's dark enough, the flash will fire even if it's "off." And it's not a nice flash, so I just put electrical tape over mine.
Yes, I do have an Instax 210 model (takes the 2x3 wide film) and it can be fun, but the Land Camera is much more satisfying. And I find the peel-apart film more fun as well. Plus, you can recover the negative of a peel-apart Fuji color print, and that is a big-ass negative! The colors can be quite different and interesting. (I can tell you all about how to recover the negative if you ever decide you want to try it.)
Here's an example of a print:

Day 130 - Zelda print by
limrodrigues, on Flickr
And the recovered negative:

Day 130 - Zelda negative resized by
limrodrigues, on Flickr
Sorry, I get all excited about instant film - can you tell?
