So glad they've come out with this. It's great to be able to cut your papers to layer and have different looks. The only thing I wish it could do is make bigger designs. Other than that, it's great!
I have drooled over all of the auxiliary blades ever since I bought my 2 In 1 Combo Purple Cow a couple of years ago. I recently took the plunge and spent the exorbitant amount required as I had never seen them on sale. This set includes, as far as I can tell, every rotary blade made for this tool. I feel this gives me more versatility in the use of the rotary portion of the tool, which encourages me to use the rotary cutter much more than ever before.
The interchangeable blades are removed and replaced very easily. They cut very well. The purchaser should be aware, however, that it is necessary to stand while using the rotary blades in order to apply sufficient downward pressure on the blade. I don't know about other models, but the 2 In 1 clamps down on your paper/cardstock so that it cannot shift its position until you release the clamp. If you do not maintain an even downward pressure on the rotary blade when cutting, it will not cut entirely through your material on the first stroke. However, because of the clamp, you can simply push the blade back in the opposite direction and it follows the exact same path giving you a clean cut.
I like to cut strips of cardstock and paper for use on my pages. In the past this has been accomplished with decorative edge scissors, which is slow and with which I tend to wander and get an uneven piece. With these blades I can select any of the patterns and get a straight cut resulting in a strip that is evenly spaced for its entire length; and I get it very quickly.
For all of you cardmakers out there, one of these blades will cut a score so that you can easily fold a sheet over.
One caution: I recommend that you test all of the blades immediately upon receipt. When I did this I found 11 of the blades to be perfect. However, the shaft of one projected too far out of the center of the blade and could not, therefore, be installed in the mount. Being blessed with a DH who can fix just about anything, I had him take a look at it. He managed to pull the shaft out without damaging the blade, found it had not been properly seated all the way into the hole, cleaned out the old glue and re-glued it. It now works perfectly.
At the current sale price which is about 1/3 of what I paid, I highly recommend that anyone who wants this set buy it now. It is great. Up-date 12-12-2009: This product is no longer on sale.