I would go by your teach then, he has seen it.

As far as I am aware all models of sax are a tuning compromise, my King certainly is. As far as tonal 'inconsistency, well I haven't heard that before. Across the register of a sax (like all instruemnts) there is a vast tonal difference we come to be accustomed to that and think of the sax in this way. It's hard to tell what he means without hearing it.

There are many non 'name' saxes available in music shops cheaper than the Jupiter - which is a mini 'name' amongst student saxes. I have bought quite a few for people, they are frequently rebranded chinese. They blow good, but resale wise, no one has heard of them so prices are down.
In the UK many want a Yamaha, so the resale value is good. I bought a Yamaha (alto) for myself, I hated it, it was bright and zingy, I took it straight back. Some people like the sound and that's great for them. If a sax is old and dirty it can add to the Kudos of the sax player, like a dirty Strat, but buyer beware.. pads and their seating.

In the end its about money,ears and condition, plus lots of sales hype

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