The difference in experience is really the only major downside to graph DBs. They're an excellent tool for many of the situations where we currently use RDBMSs, mostly because that's what we're familiar with while graph DBs are new and unfamiliar.
I've now been using Neo4J for a couple of months, and I don't want to go back. If relations between different items are what matters to you, then graph DBs make that so painless compared to the joins from relational DBs.
The main thing relational DBs still have over graph DBs is tables. Give me a table with all items from this table that meet this condition. Graph DBs can do that too, but it's less natural, because they don't store their data in tables, and nothing guarantees that all items of a certain type actually have the same properties. RDBMSs are statically typed, Graph DBs dynamically typed.
I've now been using Neo4J for a couple of months, and I don't want to go back. If relations between different items are what matters to you, then graph DBs make that so painless compared to the joins from relational DBs.
The main thing relational DBs still have over graph DBs is tables. Give me a table with all items from this table that meet this condition. Graph DBs can do that too, but it's less natural, because they don't store their data in tables, and nothing guarantees that all items of a certain type actually have the same properties. RDBMSs are statically typed, Graph DBs dynamically typed.