Usually the New Holland stuff is pretty reliable, but I have never heard anyone who owns one say a single thing good about a NH 254 or 255 rake/tedder.
As for a Haybob, I bought one years ago almost by accident. Have used it now for the last 7 or 8 years, very few problems, easy to fix. Turns out, Haybobs are the standard tool in europe for tedding hay. If you can find one they really work well. Saw a brand new KUHN, just like my old one on a dealers lot in Ramsey Indiana last year, so they are still making them. Check them out on Youtube.