The topic starters story was about the mk8 not the Tau 7.
I shoot the Tau 7s for about 10 yrs now, NEVER had an issue with either 4 of them.
So yrs is probably an owner problem rather than Tau 7 problem.
They dont have a lot of weak points and are easy to work on.
Never replaced a seal on either, except 1 piercer cap seal recently.

Yes old match can be resealed but that'll cost extra.
I know cilinder date is only an issue in matches (and for re-sale). But if you dó shoot matches, it'll cost extra.
And yes, for match use they dó require retest (steel cilinders only) or you need new (alu cilinders)

Still vote for the Tau 7 though. You can buy them new directly from the factory.(about 300 euros)

Spa also has some kinda nice 'plinker'now (its called differently in the uk). Those are VERY cheap (<100) pistols.
But no where in the league of anything else mentioned.

Reg steyr: I have the LP5. Unless yr gonna shoot 5 shots comps, its more of an disadvantage
For matches, only 1 shot mags are allowed
The young LP5's also have a different trigger (heavier)
For normal comp I'd look for an LP1
If yr gonna look for steyr, dont forget the compact. They have surprisingly good balance.