A quick review now that I've had a chance to burn a handful. They keyhole well, and the keyhole is nicely controllable. Not as fierce an arc as 5p+ which left me short of root fusion. 100amps advised for downhand open root, 1.5mm land, 2.4 ish mm gap.
Ran on ac, 475hz, they start well but do have a habit of favouring the thinner side if you grind a poor bevel, like I did.
All told, for the money, very pleased.