When I have used those in my own machine, similar to what you are describing, it tastes just like the theater.

As far as regular popcorn, I prefer Orville Redenbacher. But its about the oil and salt.

I have the same salt they put on in the theatre, but it is super strong and easy to put too much on. tzhat is why the packets are the best way I have found to get great movie theatre popcorn.