Hello Brittany, I am a great fan of the 30. I own 2: an old one with square body and a modern one with round body.
I do not feel the square uncomfortable, but I think this is quite personal.
The original 30 square body was built to be more brilliant and “clear”. The middle register (especially from E4 to C5) has much less resonance than a modern harp, high and basses are just as a modern one. You will feel naked at the beginning as the tail of the sound is less, but at the end the quality of the music gains a lot from this clarity. It works also much better if you wish to amplify the harp.
Round body examples are many on Youtube, on square body I recently recorded a CD on Hasselmans and here you can find music samples: http://soundcloud.com/floraleda/hasselmans-la-source
But also Judy Loman recorded all her CDs on a 30 square body as well as Erica Goodman (check for ex. the trio Lyra recordings and videos). I think you can get an idea of it. It’s special so you should try to be sure it fits for you.