Sanders magtech or odyssey kismet

I am looking for a "last amp purchase" one I can keep for 20+ years and pass down to my son someday.
This probably won't happen, but it is a very good possibility.

I have gone through numerous over the years, with fairly bad luck with them, UNRELIABILITY!

I have narrowed it to these two amps. I know they are both very good.

I would like thoughts on them from other audio people as yourselves.
Before you say these speakers suck, I wanted to say I auditioned A LOT of different ones before settling on these. I use energy rc-70's, only about 45-50 hours on them, nowhere near broken in yet. I LOVE their sound, period.

People say these amps are too good for the speaks, I think not.
Maybe sanders preamp.

I have heard magtech sounds thin, and others say it's amazing.

Anyway, what's your thoughts on odyssey kismet monos or sanders magtech. Thanks
Can’t speak for everyone that actively bi-amps, but- I’ve always used a crossover that enables me to adjust for disparities between amps. My first was one I built using DeCoursey boards(1980), for my home system. I ended up selling that whole system to one of my regular shoppe customers. Used a Dahlquist DQ-LP1(modded), for the next 25 years. I’ve had my TacT RCS 2.2Xaaa(modded) ever since.  I loved the Dahlquist, but- the acoustic nightmare in which I'm now forced to listen REALLY requires me to use room correction.
Bombay, Satie uses resistors to correct for power amp voltage gain differences. I still have my Dahlquist DQ-LP1, which I use for the bass leg only. Brooks Berdan tried to get me to sell it to him for the longest time, but I knew I'd need it eventually.
FWIW, I have had my Odyssey Audio Stratos HT3 for just about 10 years now. When it was new, a capacitor failed, and it was repaired under warranty. However, I had to pay for the frieght (one way, IIRC), which for a 64 lb. amp is not insignificant. Since then, however, the amp has been trouble free. And I love the sound. If it holds up as long as I do, it will be my last amplifier. Just do not feel the need to move to anything better. As for the poster who implied that Odyssey amps sound "grainy", I respectfully disagree. The Odyssey amp I have is super smooth and clean. YMMV, and you are looking at a different model. But the Magtech is $5500. For $3400, you can have a pair of Odyssey’s best Stratos Monos. Less power than the Magtech, yes, but also less money!