There are a lot of good FoxPro Callers out there. Find one in your price range and be happy. You might find the "be happy" comment silly, but knowing your personality is a big part of which caller. Truth is they will all call critters, but will YOU be happy with one of the lower end units?
I know me. I would buy one, then sell it at a loss and then the next step up within a couple of months. Then next step up will be nicer but I wanted the nicer unit and will in turn sell that one and buy another. Nothing is wrong with this approach, but don't think that you are saving a penny doing it this way.
I use to run an old Johnny Stewart MS512 and had fun with those cassette tapes back in the day. When it was time to upgrade after being out of the game for a while, I bought a Shockwave. I don't have to buy another one next month. Again, that's just my personality, if you are happy with another unit - cool.