Chinese solder wire brands?

[Monkeh]

Having said that, I do accept that a different iron and different brand of lead-free solder might well change my opinion.

Well then, I suggest picking up some samples of SN100C-like solder, Felder comes highly recommended, I find Weller is perfectly acceptable and locally available, and trying them out. You can get a little sample pack for about £8. Apart from needing a little more heat (including a touch more dwell time with more mass), I think you'll be pleasantly surprised. I find no reason to reach for leaded solder unless I'm working on a board already using it.