DSTs are the more universal file format for embroidery machines. Most will accept them from your mid range home machines to your high end commercial machines.
Wilcom's TruSizer is more for already done files. Either Wilcom's native EMB format or your raw stitch files. A caveat here, there is always something lost in conversion from either EMB to raw file or from raw file to raw file (DST to say a PES file, or vice versa). Also, even if you have the native EMB file format and yes it deals with embroidery objects (akin to vector objects), there are still limits to how big or how small you can go (and no just going from a satin to a fill or fill to satin or satin to run etc doesn't do it, sometimes it requires digitizing again for best results).
Cheap and/or easy typically means bad file. Either from a production stand point for quality output and/or efficiency of machine time. And if y'all think power trace/live trace has it's issues, imagine it ten fold in the embroidery world. Why I don't consider it auto digitizing but auto conversion. Digitizing is a key component of the embroidery process and allocated over the entire run (unless doing a short hot run) even a slightly more expensive file is cheaper in the long run, especially comparing machine run times. I've seen really cheap files take 50 minutes (and on a single head that adds up), while a slightly more expensive file takes 25-30 minutes for the same exact file.
What you'll need to know to pass on to the digitizer is size that you are wanting (this will very much affect how well the logo will translate, especially if it's "as is" only), what substrates and fabric type(s) that it's going to be going on. While it is possible for some designs to translate really well across multiple substrates, that isn't always going to be the case, even though most customer of mine like to try that first. But if you think that they are going to want it on shirts and hats (just for example) let the digitizer know that upfront. Hats especially require a very specific sequencing to work correctly in most situations.
As to what files most embroidery shops can handle, if they are using Wilcom (E4 especially), they can handle anything that DRAW x8 can handle. If they are really doing the digitizing (as in using manual/semi-manual digitizing tools, not auto converting), just about anything will work. I've digitized from sketches (usually what I do when coming up with stock designs to sell). The biggest thing is making sure it is high resolution. If doing vectors, make sure text is converted to curves/outlines. While gradients may be possible (depends on the individual situation), send the source file as a raster file, not all digitizing programs handle gradients well in vector form. Some can rasterize EPS (v8 tends to be the most accepted) files on the fly, but not all.
