I have the wider tilt shift lens - the 17mm.

It's definitely a specialty lens - not recommended unless you already have a bunch of other lenses. You might want to rent one before you buy.

It does let you play around with perspective and focus, and fake that miniature look. If you're the type who likes a different view of things, you'll like this lens.

Remember that it has no autofocus. You will have to focus it manually. I almost always use it in a tripod, and focus using Live View.

(If you've never used a manual focus lens...they are easier to use manually than an autofocus lens. Autofocus requires that the lens moves only a little to focus, and it can be difficult to manually nail the focus. Manual focus lenses don't require such fine control.)

I like taking pictures in the dark, which pretty much requires manual focus lenses. That's what I use the TS for mostly. It's also good for architecture. Yes, you can fix the perspective with Photoshop, but it's not the same, especially for very wide angles.