Greetings to Bulgaria. It seems that apnk and I have both had good experiences with the Creative flash players.
I'm in the U.S., and the V200 is not as common here as the other Creatives ... but if I remember correctly, it's the one with the built-in USB plug (sort of the Zen Nano-style "bodywork" with the Muvo-style plug built in). The Zen Nano / Zen Nano Plus is as a result even smaller (no built-in plug -- uses a USB cable to transfer songs).
I'm confident the sound quality will be the same in the two models. If the price is the same, and you need to choose one, I'd go for the Zen Nano / Zen Nano Plus (I have that one, and the smaller size is nice -- using the USB cable is not a problem for me ... if using the cable might be a problem for you, pick the other one). Also, it's possible that there are fewer firmware issues with the Zen Nano / Zen Nano Plus.
I think you will be happy with your player. Consider getting a warranty or replacement plan, though, if available to you, in addition to what Creative offers, just to protect your investment.
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To clarify, I don't listen to the radio much, so I have the Zen Nano. It cost a little less money than the Zen Nano Plus, which has an FM radio receiver.