Hey Reefphreak,
I've had the 1502 for I think 3+ years and I've been happy with it. I've got it on my 120g SPS tank and it seems to keep alkalinity & calcium at the desired levels (12+ dKH Alkalinity & 400 ppm Calcium). I have a relatively low CO2 bubble count going into it and it's still doing fine.
I would recommend, however, that you get a pump to feed the reactor unless you're gonna gravity feed it. (It doesn't work properly otherwise).
It's not the prettiest thing I've ever seen, but it's extremely durable and well-built. The Eheim has also been running fine on it for a long long time also.
Hope this helps, and good luck.
Thomas
P.S. I've read good things about the MyReef or Geo reactors, which are cheaper. I just got a MyReef Nilsen Reactor and it seems like it's well-built (haven't hooked it up yet).
P.P.S. I'm supplementing with a Nilsen because I figured if I was going to be topping off, I may as well top-off with kalkwasser to get some of its benefits.
