Sophie gets romaine quite a bit, it's her main staple for greens as its readily available at the organic market and very cheap. Because its warm right now I like her eating it for the extra water it's giving her so she's nice and hydrated. So usually it's romaine 4 days a week with other greens like arugula, dandelion, kale, carrot tops and a variety of herbs. But like it was mentioned you have to start off with just a bit in case your rabbit has a sensitive belly. I'm really lucky with Sophie, she's been able to eat everything so far without issue.