Man, this is going back some.  So turns out my sequoia, as I write now in 2020 is around 10 years old.  He's a bit worse for wear now, if I'm honest, and I'll need to get a new picture sorted soon, but pretty sure they are not going to last in a pot, and I've never had that spare money for the field!  Either way, here is back when he was a tiny seedling.  Will keep working backwards so I can eventually post how old here, but can't be more than a year or two, surely.