I am represented by Sharon and have been for a few years. I queried her with a story that was rejected. I queried her with another story and she offered me representation. She then asked to see my other works. She took on another, but passed on two others, so she is selective.
Before Sharon, I was repped by a NYC agent. I met that agent, she was excited about my story, and sent it to an editor I already had a connection with. She also told me she queried other publishers, but wouldn't give me a list. When the editor I knew passed, this agent dumped me.
Sharon and that other agent had both offered me representation, and I had gone with the NYC agent. After that fell through, I reached out to Sharon, and that's when I signed with her.
She and Ella were extremely helpful in the editing process. It took a few months, but we were happy with how the piece turned out. (The NYC agent also had me editing, but editing for a year, and giving me odd things to edit. Overall the editing process there had made me feel uncomfortable, like I wasn't understanding what she wanted of me) Sharon and Ella were both upfront and eager to discuss their comments with me.
Sharon keeps me up-to-date on which publisher has the story and what their comments are. Book #1 received multiple requests from the big publishers, but in the end was given a rejection because of various things. I had written it with a local illustrator, so we were kind of a package deal. We ended up going with Curiosity Quills Press because they agreed to take his illustrations (but then after the editing process passed on him and assigned their own illustrator).
Sharon is still sending out Book #2, but it has also gotten quite a few full requests. The most common reason for rejection is because it is too dark (I heard the same complaint from other agents when I queried the book).
(On a side note, CQP then asked to see what other books I had available. My 4th book from them came out in January. Sharon has helped me to negotiate each contract and she has offered marketing advice. I did sell those myself, but I was thankful for an agent's perspective)