If it were me I would go with the 220 over the 180. I have a 240g (advertised size, its actually 6x2x30 so basically a 220) and I just LOVE the 30" height over the 24" height of my other tanks. I love the looks of a tank that has that height because it just looks like a wall of water sitting there.
With that said, I will admit that it is a pain in the butt for cleaning algae off the front panel due to the height. I'm a big guy about 6'5" and have a long reach, but even for me I have to get a step ladder and pretty much hang into the tank to reach all the way down to clean the front panel all the way to the bottom. Mine is a acrylic so it makes it a tad harder due to the small euro brace style tops they have. So if the one you are looking at is glass that will make it easier due to the more open tops.