VA Slim- I have the 045 and you are correct, the temp probe is just that- a temp probe only.
The only drawback I've found is the connection going in to the controller was quite weak and broke. The connection is somewhere in the grass, I was going to resolder it and somehow got knocked off hte deck and disappeared.
I've been just using a BGE thermometer probe with great results. (had it before I had the 045).
I think I'd save the money.