Casio CZ/ VZ/ FZ - Pro Series

So I'm drawn to the CZ series because of the low entry-point economically speaking, and because I have a thing for Casio gear (I have an sk-1 and sk-8).

Of course, now I'm doing my research as I search for a suitable example to purchase (may have a lead on a CZ-5000) and I'm seeing all the issues people are reporting in the forum. I realize most of this is going to be because people who have working synths don't seek out internet synth guys to say "Hey my keyboard works great, thought I'd let you know," but it's still worrying to an extent

Just trying to get a gauge on whether these synths are nearing the end of their working life or if most of them are still fine? Are there any models in the line that have problems in particular? If I buy one sight-unseen, what are the chances that it works 100% vs having to tinker with it?

Just asking because I'd like t ocut my soldering teeth on something a little less complex than a full-fledged synthesizer.