Deere is pricey here.  We run trimble and ezsteer with do pretty good  on curves.  I planted, sprayed with section control on the free waas signal.  It can take a little nudging after you stop, but to get started it's pretty hard to beat the price on a ezsteer.  When I drill wheat around inside corners doing headlands the ezsteer did an almost a perfect curve for me.  We have 2 of those, but have since upgraded one tractor to autopilot and that's a whole new world.   We started first with a lightbar and section control for our sprayer.  That was a great way to learn all about this precision stuff.  The next year we added ezsteer and then we added more units in other tractors.