Seems expensive for 4'. Crimping won't kill a lot of vegetation. It works great with some plants at the right growth stage. So, if you are gong to do the same rotation every year and know crimping will be sufficient to get sufficient kill, the only problem becomes size. At 4' per pass, unless you are doing a tiny plot, it is going to take a long time. And, if you are doing just a tiny plot, herbicides may be a better answer depending on your situation.
If you have a tiller, I would probably consider putting my money into a used 8'-10' old farm cultipacker. It took me a few years to find one, but $600 - $800 should be enough. Then consider a min-till approach. Raise your tiller so that the tines are only touching the top inch of soil. When you are done the field should look green rather than brown. The tiller does a good job of chopping up vegetation and breaking the surface slightly. Microbes from the soil help decompose the vegetation once it is on the ground. This very light tillage is not going to have a major impact on soil tilth or introduce oxygen deep enough into the soil to burn OM. Any plant that would be killed by a crimper would also be killed using this method. (You don't turn your PTO off for this). Depending on what is growing and what your are planting, you may or may not need herbicides as well, just like crimping.
That is my 2 cents for what it is worth...
Thanks,
Jack