Well, both of these machines would cost me under $20, and I definitely don't have enough money to buy anything over like $40...which is why I've been searching through shopgoodwill.com's selection. I felt like these were both pretty good finds. The descriptions for both say that they power on, the pedals work, the needles move up and down. Also, based on what I've read about both models, they are very durable. So, I'm hoping there won't be much repair needed if any.
@dunster: The 128 I am looking at was made in 1918. It's beautiful, and I know there are a lot of sewers who absolutely love those old machines because of the look as well as durability and consistency. I mostly was worried about having a large enough harp...I also felt like maybe I shouldn't pass up such a find. I do want something that will be easy for me to learn on, though, so I think I'll take your advise and go with the newer 5830c...which I know is easy to use.
Thanks for the input guys! I'll be certainly frequenting this site from now on. If anyone else is interested, here's the vintage one I was looking at:
http://www.shopgoodwill.com/viewItem.asp?itemid=9513815 The auction ends in 18 hours!