I daily drive in Florida. Flat roads, no curves. I wanted to keep the ride quality as close to stock as possible so I went with H&R sport springs. Drops a little over an inch. Just enough to look aggressive but not look like a teenager going through puberty.
Hard to install? No simple, but does require some special tools to take apart the ball joints on the front suspension. There's an install guide on the forum here but it's completely wrong. If you never spring swapped a car before I'd put BMW on the harder list of car's I've done due to the front end oddity of taking the struts out, better off paying a reputable shop or a buddy that's handy with cars. You can do the rear in minutes it's a piece of cake, 2 bolts.
