Snapchat is okay. I'm coming from a Galaxy S8 Plus.
There are times (mostly on app launch) where you have to wait a few seconds for things to settle or it might lag if you try to interact. Not a big deal though.
The camera isn't that great (again I'm coming from a Galaxy S8+). And snaps get cut due to the screen size. Camera is great through the camera app though.
Switching between two animated filters can get laggy in my experience.
With that said, it definitely is usable and I don't mind using Snapchat on it (I had PRIV earlier this year and that was terrible). At the end of the day, it depends on what's important to you.
If you don't care for the keyboard and really care about Snapchat, there are same spec'ed cheaper phones out there.