Fifty dollars for a functioning used Aoyue all‑in‑one station is an absurd deal. I would happily buy yours at that price. They may not be state of the art, but they are more than adequate for basic through‑hole work. You can certainly buy better equipment as separate units, but it will cost a lot more and take up far more bench space.
I have to disagree about the value of a desoldering gun. I have gone through several types and brands of mechanical solder suckers and they all perform poorly. A desoldering gun makes removing components incredibly easy and genuinely enjoyable. Aoyue’s gun function is probably its strongest feature and holds its own against any competitor in the same class.
The hot air function is solidly midrange. It cannot match the performance of higher end models that cost more, but the internal air pump makes it more powerful, safer, and more comfortable to use than the cheaper units with the blower integrated into handle. Dave even demonstrated one of those cheaper models catching fire a few years back.
The soldering iron is probably the weakest part of the Aoyue lineup. The old 936‑style irons found on the Int 968A+ are pretty awful. The T12‑style irons used in the Int 2700 series are a huge improvement, but not on the level of the newer JBC designs.
Even so, you can always pair the Aoyue with a dedicated station for the function you use most often and still spend less and use up less desk space than you would on several separate high‑end machines.