The Tech+ has sapphire glass and a higher depth rating if you buy it up front.
It will be interesting if you can buy the sapphire glass and upgrade the mineral one

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The Tech+ has sapphire glass and a higher depth rating if you buy it up front.
I just bought the screen protector to protect from scratches. It's a nice rubbery bubble
On the installation sheet it says don't bother trying to get air bubbles out just dive and they'll be pushed out.
Mine have mostly, though I'm doing a 30m dive next up, so that should sort the last of them out. My first 3 dives were quite shallow. Max depth was 12m.