Don't talk them into a new device. I have no money for that ;-)
I don't have pixel errors, no moisture problem and I use internal sounds as well as MIDI. I do not play every day and no long gigs, so my experience may be different from other people.
But – although I do not hold back from criticizing a device or it's programming (positive and negative), I don't find much in the Sylphyo. It plays well since I got used to it.
Don't forget, there is only one programmer. Ok, this is risky, but the Sylphyo is unique on the market. If you insist on an instrument with more support and a larger user base, take the Akai EWI. For harmonica, take the Lekholm, for a plastic sax take the odisei. Like it simple? Take the Warble. If you are adventurous and don't mind a broken device every 2-3 years (if you are unlucky like me), take and old Yamaha WX7 or WX5. If you want an instrument that can react to every breath nuance and to body motions and if you do not necessarily need a sensitive mouthpiece, take the Sylphyo.
I found only one instrument that allows better and polyphonic control and with a greater potential in internal sounds, at least for my taste. The Eigenharp. But they went out of business before a general overhaul of the software could happen.
However, I am waiting for a Sylphyo update too. There are some issues and room for improvement we already discussed here.