I have 2 tillers and i don't have a garden, go figure. One is a about 50 year old JD brand with a 6hp Tecumseh and front tine. Will it open new ground? Yes. Will it beat the hell out of you? Yes. Will it break? No. Great for cultivating rows but breaking new ground with a front tine tiller is not an enjoyable event. The other tiller is a 1950's Frazier Rototiller i am in the process of restoring it. The thing is huge and heavy. Nothing today is built like it. It will break new ground easily.
If you just want to cultivate rows for weeds a cheap front tine tiller will work. If you plan on sod busting with it or reopening ground every year get a rear tine. Most of the new stuff is pretty flimsy but if you use it once a week to cultivate weeds can be worth buying. My brother in law has a 1970's Snapper RT-8 rear tine i keep running. Probably has well over a couple thousand hard hours on it. If you can find an older TroyBilt Horse or BCS tiller they are worth putting some money in to and will last forever.