Hi Jim..
When I went in for the EX1R I was recommended a kit just like yours. The 503 was on sale in B&H. That head is history now. I had a look and the heads you have been recommended on the thread and I can tell you that you should have a look at the 504, it’s tremendous.
It’s sleek, smooth, you have a camera balancing function (to do some counter-weight), it not heavy…and most important, it’s a good quality/price relationship.
have a look at it, and if you can go and see it before, for sure you’ll like it.
The Sachtler 6 or 8?…..
Sony EX1R
Manfrotto 504HD Head w/546B Tripod
FCPS3 – http://www.solwedding.com