I bought a 504R last summer.
I just saw your post. You may not have many responses, since this baler just went into production in April, 2017. Last year, Vermeer wouldn't even let their dealers order them for stock. They had to have a customer name on a sales contract to get one, and were selling them as fast as they could make them. I took delivery in late July 2017. The dealer said that mine was the first one he had seen.
Read my thread:
https://www.tractorbynet.com/forums/haying/382162-buying-new-baler-jd-vermeer.html
I love mine. The only "problems" that I've noticed have been:
1. Twine breakage. This was only when it was brand new. (less than 100 bales) And, I use Sisal twine. If I used poly, I don't think it would have happened.
2. Hard to start a roll in very short hay. My second cutting only produced 1 roll per acre. Tiny windrows. The baler clogged a few times until I figured out that I needed to double rake the hay. Once I made a bigger windrow the problem went away.
I don't think I can really fault the baler for either issue.
I hope that answers some of your questions. If I can be of further assistance, let me know. I'll try to check this thread more often.
