PDO shouldnt really be compared on the same level as MDB2, DB , etc. It is not a full fledged abstraction layer. It is a data-access package. For PDO you have to write db spefic SQL. With MDB2 and DB you use their packages lang. and that can be moved from db to db without having to rewrite the SQL as you would if you used PDO.... OR at least that is my understanding.

I have been wanting to move to using PDO, and have no real idea when I would need a different DB, but it just seems that if you are writing it, why no make it as portable as possible?

And since mysqli makes use of bound parameters (and pdo using db specific sql anyway), I still cant figure out what the benefit of using PDO is?

If you can provide any feedback that would be great.

Thanks.