I just hooked up my XP3 today, and am very happy. It was so easy, and the instructions easy to follow. They give you 2 hoses as well, and I only had to use 1, as the height of my tank stand isn't real high. I have about 25 inches from the top of the filter to the water level in the tank, which is nice. I just cut the correct size for the intake hose, and it was less than half the total length of the hose. When I did the output hose, I had to cut about 8 inches off the remaining half of the hose, and hooked it up. So I still have the 2nd hose if I ever need to replace anything. It was very easy to prime too, lift up on the primer on top of the filter, remove the cap on top of the intake, place the funnel in and fill the tube. Put the cap back on and push the prime handle back down and it automatically fills the filter. Then plugged it in after it was full and it's so silent. With my head under the tank, there's a slight hum, but when I close the door, nothing. All I hear is the water flow from the Emperor 400. It's so nice and easy to set up. So my opinion is go with the XP series, you won't regret it.
With the XP3, I use 2 coarse sponges, 2 finer sponges, in the lower basket. The middle basket I have cylinders and lava granules. In the upper basket is my stars media in the lower half of the basket, and in the upper half I'm using 2 of the fine particle filters, kind of like floss, instead of just 1 floss with the packet to remove nitrates that's supplied.
For the output, you also have a choice. You can either use the power jet or the spraybar, with all the tubing. I didn't need to use all the tubing either. I went with the spraybar for my tank.
So there it is. The XP1 only has 1 basket, the XP2 has 2, and the XP3 has 3 for the ultimate amount of filteration media. I think I'm really going to like it.