Hi and welcome!
I also have a 270D and I can tell you that it pieces a very accurate 1/4" seam. In fact, it is more accurate than my other machines, so I use it almost exclusively to piece tops. This is using the J foot, I believe.
Also, it will not work with any hoop large than the 4 inch hoop it comes with. It will work with a couple of the smaller ones, but nothing larger. If you wanted to make a larger design, you would have to break it into sections.