I bought an EBJ900K last year for less that $100, it too has a fair amount of slack in the guides and like you I took ill to the very hard springs. In the end I took one of the springs out and found it a lot simpler to eliminate the play in the guides by hand. The down side is how much is shuffles around on the bench when your trying to make a slot by eye
I've made a few projects with it and never took much issue with it's short-comings. Works well enough for a sub-$100 unit.
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