I’ve had good luck with ESUN PLA+ here, but I’m in New Zealand and using a printer with 2.85mm filament so my options are extremely limited.
One thing to bear in mind is that ‘stronger’ isn’t necessarily better for what is recommended here. As far as I understand it, it’s stronger (tougher would probably be a better technical term) because it’s slightly flexible which leads to it being less brittle and prone to cracking apart under load. Ryan has said a few times (including in a recent comment I saw somewhere) that he prefers PLA for the rigidity and doesn’t find any of the advantages of PLA+ to be useful here.
It has worked well for me, but I’m one guy with one MPCNC that I’ve never pushed particularly hard (it has aluminium tubes that are half as stiff as the conduit ones, anyway). I have nothing to compare it against, so all I can say is that it’s definitely possible to get good accuracy and reasonable performance out of a machine printed in at least one type of PLA+. I don’t have anything to compare against, though, so that doesn’t necessarily mean anything!
I haven’t noticed any differences in part rigidity when switching from PLA to PLA+, but I’ve definitely noticed that it seems a little easier to print with and the parts are somewhat less brittle. The problem is that printing with ‘wet’ filament that has absorbed moisture from the air can also produce similar changes, so my going from old PLA that I’ve had for years to brand new out-of-the-box PLA+ means that it wasn’t remotely a fair comparison.