Bowflex dumbbells

Well, I've had the 552's for about a year and a half. I would say they are the best investment in fitness equipment I've ever made. You can slam them down, dial them up to a different weight and crank right back on with the next exercise. You can get a killer workout by getting the weight you actually need to push a particular body part without having a full rack of dumbells taking up a ton of space.

Before I had them, I didn't have a full range, so I tended to compromise on body parts where I didn't have the right weight. Now I can pick the right weight all the time and make serious progression by pushing myself.