COIZ, YOU ARE THE MAN!
You even show the file!
If you don't have a file and an inside the tubing reamer
to remove burrs, don't bother starting!
Nothing like a burr getting turned and screwing up an otherwise perfectly serviceable flair!
The best advice I can give you...
Unless you are using an $800+ hydraulic rig with heavy self centering 'Taper' turner, (Large 'Jig' holder to keep things in place)
Then don't GORILLA
the flair when it's inverting!
You are only there to turn that flair mouth IN and smooth the tubing down,
Not flatten out/expand the flair until it won't fit in the female part of the fitting,
Or to mash out/crack the tubing!
You have to turn the taper in, but leave a little bit if 'Give' in it so it can conform & seal to the female side of the fitting, and it does that by distorting slightly...
If you mash it's guts out, it's work hardened, and won't deform to seal with the steel fittings in some cases, and others it will be mashed out so large it won't even fit into the fittings...
I've not had any problems with those $30 to $50 hand sets like the one you show.
I've done MANY vehicles from farm tractors to race cars with them, and not had any problems that weren't my fault,
(With the exception of 'China' tubing that was an odd outside size and WOULD NOT lock up in the clamp block! MADDENING!
I still carry my little kit like that in my 'Field Work' tools.
Took it to the 'Jeep Clinic' and showed a couple of forum users how to flair their own lines, and they did their ENTIRE VEHICLE with it!
(I'm sure it was hard on the hands with all those fittings/flairs, but it did the job over time, and did it well for about $40 or so!)
Works FINE for two or three fittings when you don't have a shop full of tools to work with.
No issues what so ever with them, no matter what anyone else says!
Great for the 'Home' shop that doesn't want to pay $800+ for a hydraulic flaring set.
The biggest problem with stainless steel lines is they are HARD TO FORM!
You will break your hands and ruin a LOT of expensive tubing trying to do very many stainless lines with a little kit like that!
When we went to all Stainless Steel lines at work, it didn't take me long to buy a $1,200 kit that had HYDRAULICS!
Saved my old man hands and REALLY made stainless work a snap!
BTW Coiz, you make VERY good looking flairs!
I don't think mine ever looked that good with the little hand kits you show!