I haven't found head to head studies, but Tirz providing roughly 50% better improvement in insulin sensitivity at equivalent doses looks like a common result.
View attachment 308839View attachment 308840
Honestly I'm not sold on Reta as anything but having a potentially higher max weight loss. While the "no fatigue like tirz" component seems at odds with what the trials show.
I think fatigue is common with both Sema and Tirz during the first 6-8 weeks, sometimes longer, but eventually resolves for most and by the time someone tries Reta they're mostly beyond that point.
I had massive fatigue on Sema, which eventually stopped, and never experienced it by the time I switched to Tirz.
I could be wrong. The glucagon effects in Reta haven't been nearly as deeply studied as GLP/GIP so maybe there's something there.