Today I decided to take the plunge and let DD try to take a nap in her big girl bed. I tucked her in and I sat in the bed with her for a bit and read her some books. Then I explained that she was going to nap in the bed and that she needed to stay in the bed. While I was reading, she even started sucking her thumb and closing her eyes. I thought, "this is going to go off without a hitch!".
I left and kept an eye on her with the video monitor. She laid there for about 3-4 minutes and then decided to get up. She went to her drawer to start taking clothes out. I went back to her room and put her back into the bed. She went in with no problem and laid down. Then I left and within 2 minutes, she was climbing back out of the bed and going to her drawer to take out clothes. We did this a total of 4 times and then I threw in the towel and put her in the crib.
So, I'm going to take the approach that "if it's not broke, don't fix it". She sleeps fine in her crib and except for her fussing sometimes when I first put her in, she does fine. I may try again in a month or two but for now we are staying with the crib.