Rusty don't worry about the Topre going out. Topre puts a great deal of effort to make each of their keyboards.
Sure they don't have all bells and whistle especially if your plopping down 200-300 dollars for a keyboard, you'd expect more.
But the Topre should last indefinitely. The fact the domes can be swapped you could probably, if Topre ever sold dome/mat replacement kits, it would last until the electronics wear out.
Topres are considered about 30 million actuation, either way you still got decades of use. I think this is the problem with the whole "mechanical factor" it puts too much of an umbrella term over everything. And some just focus on "Oh it's not mechanical, nevermind".
Remember Topre is a quintuple hybrid switch encompassing many of both worlds.