I'm pretty frustrated with the Mangrove Jack's yeast. I've had almost every beer under attenuate, even with oxygenation with pure O2, mashing low, doing step mashes, etc. The only beers I've had attenuate properly were an Oktoberfestbier and Schwarzbier, both finished at 1.014. The Newcastle Dark finished at 1.016 on a 1.038 beer. And repitched into an oatmeal stout it finished at 1.024 with an OG of 1.059. That was also oxygenated with pure O2, mashed at 154 for 90 minutes. ANNOYING. I have a faux helles fermenting now with Workhorse at 64, I hope to hell that beer gets down to at least 1.012.
I think it's either liquid yeast or the occasional US-05 or 34/70 for me, here on out.