I wouldn't worry too much about your Tiptronic failing on you again,that doesn't happen much on these cars.
I would worry more about RMS leaks(not so much on a Tiptronic),o2 sensor & MAF wearing out & wheels bearing replacements on a 97'. None of which should cost anywhere near as much to fix as replacing your Tiptronic.
I'm sure you'll be fine in the end.
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-99' Zenith Blue 5-spd...didn't agree with a center divider on the freeway
-01' S Orient Red Metallic 6-spd...money pit...sold to buy a house