Although I read alot here , due to time constraints , I usually do not post , but since I have my Semi parked for a few days , I'll give you my opinion .
You pretty much hit it on the head being that tillers are 1 dimensional . My neighbor and myself have TC-30 NH tractors . He bought a tiller , ( believe its a 72" ) and although he has used it a few times in his lower field area and it does do nice work it just a couple of passes , the tines take alot of abuse in non-garden type applications , ( rocks are pretty hard on tines ) .
Were as I bought a 72" king cutter disk and have used it pretty extensively for over 3 years now with little damage to any of the blades / disks themselves . It does require a few more passes to get good depth and soil break up , but in the end you would be hard pressed to tell the difference between what was disked versus what was tilled .
I disk down both sides of my driveway to keep weeds down , ( both sides are roughly 25' x 800' each ) , plus I do a 12' border on the south side of our property and the west side for fire protection , ( west side is downhill from home , while south side is both downhill and the normal direction from which the afternoon winds come from ) . Last summer , while I was disking the driveway , he was tilling a section of his field . Although his field came out looking pretty good , since tillers leaves no tracks , I can only imagine what the tines looked like since it was virgin soil . But 2 months later the amount of regrowth was identical both in his field and next to my driveway . So in my opinion , the tiller did no better job working the soil than my disk did . Also after a few passes , my disk will cut just as deep as most tillers will , with alot less strain on the tractor .
If you were looking at a bigger garden area , then maybe I would look at a tiller , but for the size you are stating , I could not justify the cost difference between a disk versus a tiller .
Take Care ,
Fred H.
