I like oil finishes much better. Tung, teak, linseed what ever. Varnish before poly any day. They touch up much easier and are just as easy to apply. Also you can make your own, its much cheaper. Even if you do go poly just cut it 50/50 to start with then you can adjust to your liking.
Either way nice even thin coats and steel wool in between like jsweka mentioned.