I hesitated and only checked out Premast on the third thought. Not even the second. The thing is, I've loads - and I mean loads - of Powerpoint and Keynote templates. The same goes for Word, Excel, Numbers, and Pages. Some came bundled with AppStore apps (Jumsoft, Graphic Node), others are through similar lifetime deals such as the one presented here: namely Kroma.ai (formerly Slideshop), Slidebean, and Decktopus, to name a few.

At first glance, Premast looked more of the same, and the same I don't need. Indeed, forget about the "free and premium templates" that come with this LTD. They're nice but essentially "more of the same." Nothing outstanding.

The real deal is, without a doubt, Premast Plus. And it's a big plus that I've only come to appreciate once playing around with the service and installing the PowerPoint Plug-in. Premast Plus has several features that I've been yearning for, looking for, and didn't find with any other offer to this date:
Simply integration with PowerPoint.
Ease of use and quick access to my slide collection directly through PowerPoint
Brand Kit: It just rocks! All logos, colors, images at my fingertips. In PowerPoint!
Collections: I can sort single slides into a range of groups and define my categories.
Asset Library: Like other templates on the market, but nice looking and quickly available through the same plug-in.
So, overall, get Premast Plus and take the free and premium templates as icing on the cake.

One concern: Sumolings get access to TWO sites: Premast Plus AND Premast Templates. Templates were there first, and Plus is the new product. The fact that the two AREN'T linked under the same site with the same access through login and password is cause for concern. Premast simply could introduce another third site to the mix in the future. I'd also prefer to have all Premast templates and account settings under ONE login. Merging the TWO sites into ONE would help. At the moment, Premast Plus is my sandbox, and I've hardly glanced at Premast Templates.