Which Planet? The original or the Planet 2000?
I have owned all three -- original Planet, Planet 2000, and Apollo.
In my opinion, the Apollo offers the best sound--musical, smooth, non-irritating. I found the 2000 model a little rough and ragged. I still have the original Planet in an office system.
I think the original Planet is more user-friendly than the Apollo. The CD well is easier to use. The Apollo has a 14-15 second "initialization" sequence that it goes through when you insert a disc. I didn't like this, but clearly it's not a problem for thousands of happy Apollo users.