I've seen it played locally but am not playing it myself despite my interest. While you can play with just the (admittedly full featured) core book, not releasing a dedicated core three book set probably didn't help it.
That also isn't something Paizo does. With good reason- there isn't much reason to do a 'DMG
' style book that immediately suggests its aimed at ~20-25% of the customer base.
My take on Starfinder itself is pretty poor.
-I dislike several of the few classes (design approaches, abilities that don't really function or don't function out of combat- mechanic has several of both, which is shame because I like the idea of the class, at least the integrated AI variant), though nothing galls me more than the mystic. Every healer has to be a god-botherer with limited telepathy for no reason (despite that most classes get to choose class features as they go, this one doesn't. And they're themes are largely terrible, and sometimes outright offensive. The goddess of all things Noble and Good sponsors mind-rapists just like the evil gods of monsters and S&M. Er... whatnow?
Not that healing really works well in SF
- if a party member doesn't have all their stamina blown away and hasn't started taking HP
damage, healing doesn't do squat.
-some systems were just left unfinished (and are also mechanically bad, see archetypes),
-editing and layout is kind of a mess with a fair amount of contradiction (you can see where they changed their mind on some rules, but missed erasing it entirely, like dex to damage) and
-a lot of cross-referencing and page flipping is required (lots of see rule x, and lots of rules that look like they apply but don't (thrown grenades don't function like thrown weapons), or have an important clause just tacked on at the end (like automatic fire: surprise! it's terrible and also takes a big penalty to hit if you read to the end)
and the some of the rules just don't work (the scaling DCs
for starships- you actually get worse at piloting your ship as you upgrade it).
- and a lot of change for the sake of change from Pathfinder, some of which is better, other elements are just weird and a fair amount is worse.
-Combine with the 'this tall to ride' weapon ratings, the weirdly scaling damage that really doesn't match enemy HP
, and pop-gun starting weapons. And every class is best served by burning feats on rifles or something (proficiency and specialization) as most of the classes don't have combat options that are better than just shooting fools.
- a lot of weird setting/mechanics tie ins (everyone is in a spacesuit always, because all armor explicitly is a space suit and they work even when broken, so vacuum and environmental effects are basically never a problem)
-and the setting itself is... bleh. Multiversal simultaneous mindwipe even on the most powerful of beings, and every mystery in the galaxy is basically present in the home system, with layer upon layer of old gods, to the point that the High Priest of Nyarlathotep is a great and admired hero for fighting off Even Elder-er Gods.
- and a lot of basic genre tropes either don't function or are absolutely mechanically poor decisions. Heirloom laser sword? Nope, chuck it for the next upgrade. Personal sidearm like a Blastech DL
-44? Nope, chuck it. Go into debt for a starship upgrade? Nope, can't buy ship bits for money because fiat. But they will come free when the party levels, so don't worry about it. Want to arm soldiers for dangerous combat? Tough, they're too low level to have real guns, break out the pop guns and watch 'em die horribly. So what if they're elite guards for the actual weapons manufacturer- the levels don't match, so nope.