I used a panning Benro ball head of my dads last year, and it was enough to convince me to avoid that option when I bought one for myself. It's just too many levers/knobs for me to try and manipulate by feel with my eye to the glass and it was really hard to control the panning tension.
I'm perfectly happy with a regular ball head, and the Manfrotto 494 is pretty smooth, but if I thought I wanted to do lots of panning I would go with a fluid pan head of some type. The advantage of a ball head in my mind is the ability to get them in a lighter weight and compact size. The 498 is both big and heavy, so not a direction I would go.