Im not familiar with erskine. Around here its dutchman, caretree and lemar.
I lean towards dutchman. Hard to beat for durability, reliability day in, day out. All edges are round or have been rounded off also, saves on tree-shrub foliage and bark.
Lemar boast all of the same features. Second only because of price, they kinda the rolls royce of spades.
Caretree well, seen more of these sharp edged every were things with busted hinge pins, bent blades and quickly wearing nylon 'slides'. But they are affordable and number in the 100's around here.
I know of three tree farms that have left caretree altogether and went dutchman.
I have only eleven years in this gig and sub-out my digging But, I am very involved with the digging from operating the spade, to pinning and crimping and loading trees.
A lot has to happen in a short amount of time and a bum spade REALLY kills the moment that needs to happen.
JD790 with 300 loader
Lots of implements for lawn installs and MANY other compact tractor duties