Thanks for the replies. I think I'm going to do personalization for the agents that I'm really high on (and try to keep it relevant).
However, I just can't find the time to do it for all of them. Especially, when a lot seem to be going into agent's Spam box.
I've gotten 5 replies (3 R's, 1 full, 1 partial--both turned into Rs). Two of the R's were marked as spam (apparently some agents do check their spam folders). I even had one that I cc'ed myself turn up in my own spam box.
I started with big agents, who are known for quick replies (like Stephen Barbara), but most haven't replied, which leads me to believe a good portion of my queries are marked as spam.
I've found some 'best practices' for avoiding getting your query marked as spam (here's a good list if you are interested:
http://querytracker.blogspot.com/2010/07/dont-be-spam.html).
Thanks for the feedback, and support. I've pretty prescient, but I think I would have given up long ago if it wasn't for the support others have given (a lot of it from everyone on this board).