I think the Andersons spreaders have a better impeller (two straight fins and two curved fins which seem to throw for a mile...well, about 14') but the Shindaiwa has a few features that the Andersons spreaders don't have. It has an adjustable chute that drops the fertilizer on the impeller which I can't say if it is good or bad yet, I'll have to run some tests but I like the idea (the Andersons spreader has a cone that drops the fert onto the impeller which works very well but I don't understand the purpose). The Shindaiwa also has the frame off of the hopper on the front which allows you to lift it on and off the truck, very nice touch!
I'm running it on Monday so I'll be able to dial it in and give a better review. Can't wait!