20/20 is better for seed, it does many little things better and uses different logic in controlling somethings.  They now do yield monitoring.  But Ag Leader does giudance.  If you want an all in one that makes Agleader the only choice.  If you are not going to do guidance the only choice is 20/20.  I love having the fieldview on my Ipad.  It triples the worth for me.  I loving having it for scouting and for harvest.  If I could get a red yield monitor I would as I would be able to have my yield maps with me anytime anywhere.  My personal preference is having 2 monitors, because each monitor has a lot going on.  That costs more, but it is also how it happened over a few years here.  These are just my opnions.  Many on here have very good luck with agleader.