I don't use SF1 but we have planted with the Outback S and eDrive which should be comparable. The agrivating thing about it is it will work well enough MOST of the time it really gives you the itch to plant with it, only do disapoint when all of the sudden a bird goes out of view or something and the guess row suddenly either goes to 10" or 50". Or after working for hours with maybe 6" variance in the guess row and being almost acceptable the sun starts going down and the guess row goes to either 10" or 50".  Or something else or something else. A lot of the time it is acceptable if you aren't expecting perfection but the other 10% of the time it just makes you want to hide thinking what kind of crappy farmer the landlord is going to think I am. Planting straight isn't the problem. Keeping the guess row within reasonable tolerance because of the inherent way the gps correction works is.

I honestly believe as WAAS improves it will be possible to plant without RTK or subscription corrections like SF2 in a few years. Recievers are getting more powerfull all the time and I think it will only be a matter of time before they have software and hardware that will do the job "free" as long as you do not need repeatability. In the meantime there are the subscription corrections or the Outback Baseline (single frequency RTK at a more reasonable cost with reduced accuracy than dual frequency RTK) with no annual fee but an upfront cost.

John