I have both, and 130 and 140 w/Fast Hitch. This particular year I cultivated with the 130 and hilled with the 140. I'd just put the cultivators on the 130 and was experimenting with it.
The County has a farm park where they let us plant vegetables for their Fall Harvest Festival. We normally plant around 250-300 lbs. of potatoes. I got designated to cultivate and hill the potatoes, so mounted the hiller (converted from 3 pt. hitch) on the 130 so I could do both. Cultivated in first gear, hilled potatoes in second. It worked great. Hiller disc's are 15" and didn't even know they were on there.
But we plant 5' O.C. I suppose in all there is about 3/4 of an acre planted in potatoes. Rule of thumb here is for every 100 lbs. planted you get 1,000 lbs. in return. I have no idea the amount you want to harvest, but guessing with that planter you should be able to plant 500 lbs. and in a good year, harvest 5,000 lbs. Just some food for thought on considering 5' rows. Here again we use an old IH pull type digger and is pulled with a small New Holland tractor with hydro so it can move slow.