What to get as a first time incubator depends on your long term goals. You've had chickens for a few years, so I am assuming you will be hatching more than one or two batches, possibly selling chicks? Styrofoam incubators can work, they just take a lot more babysitting. Amy has great results in hers, but she sleeps much less during those 21 days than I do using a Brinsea. I work long hours, and I needed something that was on autopilot, so the Brinsea was worth the money for me.
For a budget of $100 or less, I would buy the best styrofoam I could afford. I agree with Amy, the LG9300 is horrible. I would look for a Hovabator
$100-200 I would start looking at a loaded to the gills Hovabator, with auto turn and all, a Brinsea Mini Advance or a Brinsea Eco20. The Hovabator will have the highest capacity (48 eggs), but will require more attention. The Mini Advance has the smallest capacity (7eggs), but you plug it in and it does all the work. The Eco20 requires you turn the machine to turn the eggs, but is an extremely stable environment. The other plus to the Brinseas is they come with a 2 year warranty, and are extremely easy to clean after the hatch, but you are paying a good deal more for a machine with less capacity.
I hatch and sell just enough chicks to cover the cost of feed, so I opted for the Brinsea 20 Advance. Extremely dependable, and easy to use with the auto-turner, but costs $360-380.
Your long term goals and initial budget will make the decision for you