Camo,
I bought one last year and its awesome! I'm not really worried about down speed on the lake that I fish because currents aren't to much of a factor. I spent last weekend running my Dipsy's with it attached to them at different speeds at 120, 150 and 180 out on the wire and it tells you what depth your dipsy's are running at. In my opinion if you can't afford the down temp and speed units the TD is definiately worth the $.
Tom