I had been wanting to try Infrared for some time, but always kept putting it off. Finally, I bought a few books and studied for a while, then took the plunge. Let me summarize what I've learned.
1. The term Infrared photography has two meanings. One is to gather heat images. The other is to gather reflected IR light. We're talking about the second here. The first takes completely different equipment.
2. Make sure your camera can take IR. All modern digital cameras have a filter over the sensor that blocks IR light. Some of them are far more sensitive than others and the ones that are too sensitive make using a filter like this impossible. There's an easy test. Grab your TV remote and set up to take a photo of the business end of it (as if you were going to use it to control your camera) then press any of the remote buttons while taking a photo. If you have live view, you don't even need to make an image. What you're hoping for is to see the IR light from the remote. Ideally, it will look like the light beam you'd get form a very tiny LED that you might buy for a keychain to use at night. More is better (shorter exposure times). If no IR light is present, stop here or use a different camera.
3. Now, get this filter in the right size for your lens. In my case, my SLR blocked all IR, but my Canon G12 was fine. I bought the filter adapter for the G12 (which I also use for other filters, such as a polarizer) and I bought this filter.
4. It will be hard to compose and frame your images. Use a medium or high F/stop and set your camera to bracket exposures if it has that feature. Pick something far enough away so that you can manually focus on infinity. If you really want to focus closer, get a measuring tape. Either way, manual focus is pretty much required.
5. When you take shots, they'll appear in shades of red when you first look at them. If your camera has a setting that lets you see images on its LCD in monochrome, you can use that. Either way, you'll have to convert to Black and White in some editing program.
6. I use Photoshop and Nik Software Silver Efex Pro to do my IR editing. You can start with Google's Picassa for free if you're just getting started with photo editing.
7. One of the major benefits of IR photography is that the best IR times are mid-day, which is usually the worst time for color images. The opposite is true, too. Great morning or afternoon light won't usually give great IR photos, tho there are notable exceptions.
All in all, I'm very happy with IR in general, and with this filter in particular. As with all filters, it makes no sense to put a cheap, distortion-prone filter on an expensive distortion free lens. Tiffen makes quality filters. You can pay more for other brands, but there's no need to do so.