The Ariel Opal is a very nice toilet but it is difficult to install.
It is very elegant, and looks great in our bathroom. It is a mix of modern and traditional styling.
It flushes very well, much better than my old 3 gallon toilet, and now I'm using a fraction of the water which is fantastic!
I had the following problems with installation, I was able to figure out how to install it without instructions (toilets are fairly simple):
1) The outer diameter of the drain is larger than the largest standard American drain (4"), which meant that I had to have a plumber cut my drain flush with the flange so that the toilet would not rock.
2) The screws provided were too long and stripped easily. They don't need to be more than 1.5 inches, the extra 3/4 of an inch are overkill, and a major pain as you have to screw them into plastic, which is always very difficult. Buy yourself #10 stainless 1.5 inch screws.
3) The stainless tubing for the water connection provided was not useful. Buy yourself a tube that will fit your valve, and go to a standard american faucet (it uses faucet not toilet size for the water inlet to the tank). Because of this, I am going to buy two sets of replacement parts, in case they stop importing Ariel.
The toilet is Chinese, but it is not "cheap crap" as another reviewer said.