Well I already own a Kubota 2920 (29hp diesel) with a FEL and backhoe so that eliminated the 500/700 series. I don't need any of their beyond lawn tractor features since I have the Kubota. I just wanted a lawn tractor to mow my 1 acre with a rear bagger that was lighter than the 2,000 lb Kubota which is like driving a steam roller across the lawn. So that put me into the 300 series.
Since I would be opting for the rear bagger I wanted all the HP I could get so that eliminated a bunch of 300 series. I went with a 48" deck again knowing the rear bagger would be consuming some of the HP plus I have a 60" deck on my Kubota and that has proved to be too wide. I did not want 4 wheel steering which eliminated a bunch more 300 series. That left the X320, X380, and X390. The X320 doesn't have the new Accel Deep Deck so that eliminated it.
So it was down to the X380 or X390. All you get for the additional $1,000 on the X390 is the hydraulic deck lift and power steering. Not worth $1,000 more imo. The foot operated spring assist deck lift on the X380 takes minimal effort and there is a lock on the dash to lock it in the up position. I operated it a few times and there wasn't anything to it. They have improved the manual steering on the X380 it steers with minimal effort plus I have popeye forearms it won't be a problem. That I'm eliminated the possibilities of hydraulic steering and deck lift issues in the future, a bonus.
I have hydraulic everything on my Kubota, at 2,000 lbs with the mower deck and north of 4,000 lbs with the FEL and backhoe power steering made sense. The 60 inch deck weighs a lot so again hydro's make sense. For this little X380 it will be fine.