I've made several small sites with it. It used some great ideas like the data model been totally flexible while easy to use and xml + xslt as server side templating was nice to use. The in-browser developer tools were good too.
Unfortunately there were also a bunch of bad points that never got fixed. Breaking changes for pluggins exhausted the small contributors community. I think the project is basically dead at this point and I've moved to another cms for small sites. (Keystone.js)
All in all, if i were to rewrite symphonycms now, i would drop xslt in favour of jade or something less anoying to writte in.
EDIT: I've been browsing symphonycms repo after writting this and it's untrue to say the project is dead since Brendo is still actively commiting.
Unfortunately there were also a bunch of bad points that never got fixed. Breaking changes for pluggins exhausted the small contributors community. I think the project is basically dead at this point and I've moved to another cms for small sites. (Keystone.js)
All in all, if i were to rewrite symphonycms now, i would drop xslt in favour of jade or something less anoying to writte in.
EDIT: I've been browsing symphonycms repo after writting this and it's untrue to say the project is dead since Brendo is still actively commiting.