My findings below...
This Landscape essentials package came with a ton of presets and brushes. I really only scratched the surface of them after playing with them for a couple of days. There are certainly some fun and effective options in here for reducing editing time. Installing and using these are very easy.
Some of these presets look great until you actually view the photo at 100%. If you're printing or posting high-res images, you need to really pay attention to the details. Occasionally a preset will be very heavy handed with the shadows or saturation and you will end up with a ton of noise or color aberration. These issues can be mitigated by further tweaking of the regular lightroom tools, but it will cost you more editing time. I personally did not like some of the more extreme presets. There are a few that try to emulate film stocks by putting washes over your image, I think these look way too unnatural but some people might like them for the very reasons I didn't.
It's hard to have any universal expectations of how some of these are going to work. A preset that works great for a particular photo may not work well for a similar photo. Not really an issue as you can just undo any application in no time. Some presets will utilize "Lens Corrections" to transform the shape of the photo. If this produces an undesirable effect, simply go to lens corrections, basic, and uncheck "Enable Profile Corrections".
I think if you like working with presets and don't enjoy doing everything from scratch, you'll probably have fun with these. If you're cranking out a lot of stylized images, these could potentially save you some time. Also, if you're new to lightroom and perhaps a little intimidated, these may provide some added comfort because they do a lot of work for you, and you're still able to fine tune from there. That said, I still very much enjoy taking my time to craft an image manually. I'll leave you with one more example below and thank you to Sleeklens for letting me try these out!