I've had two agents so far. The first one was one of the first batch I contacted from a list I made from the Writers Digest agent book, and the second was a friend who had his own publishing house for a while and then turned to agenting. The first one has decided he doesn't want to represent me any more, and I'd rather have the second one's friendship than work with him.
So, at a recent writing conference, I booked 15 min. with each of three agents. One of them looked at the samples I had with me and talked to me briefly about my subjects, and decided then and there she couldn't help me. Another wanted to see my children's book, and a couple of months later returned it saying that she didn't "feel enthusiastic enough about my ability to market your manuscript successfully to offer to represent it." The third was eager to see everything, but when I checked the Editors and Preditors page, I was inspired to ask him a few questions first, and based on his replies, decided not to send him any of my stuff.
But the last night of the conference when I was enjoying a drink in the bar, I fell into conversation with a woman who turned out to be an agent, and she's looked at one of my book proposals and is mailing a contract this week. She also says she's "marked up" my proposal so I can revise it again.
I think what's important is that you believe in your work, and that you believe in yourself as a writer -- a professional who can not only take but use criticism for the benefit of the work itself. Consider everything people say about it, accept what you know is right, experiment with what you're not sure of, and let go of what's ignorant, mean or unconstructive. (It can take some "inner work" to create that relationship with criticism of your work, but it's worth the effort.) With that attitude, if you pursue every opportunity to meet the right agent, you will. Use the time it takes to polish your ms. and your query letter. Don't give up!
Blessings,
Ashleen