> The cheap-o $15 soldering irons all produce horrible results and will shatter your confidence...
I would make the opposite argument that if you can get great results from a cheap-o soldering iron, your confidence and ability will soar thereafter.
Recall that, back in the really early days, soldering irons were large affairs, consisting of a large block of copper heated via a gasoline or kerosene torch, with a large wood handle and a steel shaft:
https://www.stevenjohnson.com/soldering/pics/old-reliable.jp...
Electrical ones weren't much better:
https://www.stevenjohnson.com/soldering/pics/ge-1911.jpg
Now granted, connections were mostly "free-air" and not PCB based or similar. Also, some of those irons were meant for soldering sheet metal, not really electronics or electrical work - but that's what people had at the time...
When I learned to solder thru-hole electronics, I learned with what could be called a "cheap-o" soldering iron; something like this (maybe not as nice looking):
https://www.circuitspecialists.com/content/image/104526/600/...
I still have it, and still use it occasionally. It takes "forever" to heat up (about 10-15 minutes), and the tip looks like hell. But for thru-hole construction, it works great. Once you know how to use it, you can solder like a champ.
Would I use it for SMT rework? No. Basically it's virtually worthless for anything with less than 0.1" pitch, unless you're removing parts and just need to dump a lot of heat in a small area.
The key to successful soldering is knowing how to control and place the heat where you need it, and flowing the solder into the joint properly. Most make the mistake of not tinning their iron or the part leads, then trying to flow the solder using the tip of the iron, where all it does is stick the iron tip. Instead, you have to heat the component's lead(s), and flow the solder using the heat on the lead(s). Tinning both the iron and the leads helps with this as well. Flux can also help, but if you use a decent flux-core solder (preferably 63/37 ratio tin-lead), flux should rarely be needed. A paste flux is useful though for cleaning the tip of the iron, especially when shutting down for the day.
It's kinda like arc welding. Sure, MIG can be easy to learn. But if you really want to understand, start with rod (stick) first. Yeah, you'll stick the rod continuously, cussing a storm up at first. But after a while, you'll develop the knack of keeping that weld pool just right and moving the rod while feeding it in, without sticking. Once you've done that, MIG is nothing...