So I have a $10 temperature controlled soldering iron that I've been using for 6 years. It's potentiometer and triac controlled, and uses 900M tips.
I solder a few boards per month on average, both SMT and through hole, but occasionally do a 10-board job for pre-production design verification. I am still on the original tip that came with it, which is a conical tip with one side sanded, and works well for almost everything from low pitch QFN to through hole.
This has served me well and gets the job done with no fuss, but for soldering big RF connectors the thermal response isn't good and I have to use above 350C and take more than 5 seconds. I would like better thermal response which would allow me to cut down on time spent per board.
I would like to upgrade to a "proper" soldering station, but it seems a big jump to go from a $10 disposable iron to a $200+ station. I first surveyed what is available locally. The higher end ones average $50, and use a tip construction like this (they call it "500M"), which seems to poke a thermocouple close to the top of the tip (?):
My question is how much thermal performance improvement can I expect from a tip construction like the above, and what else besides thermal performance does a "name brand" station like Hakko or Pace offer over my $10 iron to justify its cost? (and don't say "quality" - I know how to weed out shit crap on taobao and get something that lasts a decade, which I'm sure my $10 iron will).