I want to start off with the caveat that I haven't ever personally dealt with a Melco machine. All the feedback that I have received is over the years from my digitizing customers that have had those machines.
Biggest Pro that most people talk about is "auto tension". I put it in quotes, because it's not totally auto. Let's say you have it set at 7 for tension, but the
computer senses that it more or less tension, so it might move down to 5 or up to 9. But any more then that range and you'll have to go through the software and change it that way. They just no longer have the manual tensioners as well. By the way, those numbers are just for this discussion only, they aren't "hard" numbers.
Biggest Con to those machines is vibration. Now all machines (depending on upkeep) will get this to one degree or another over the years. However, I believe that it happens quicker with Melcos due to high spms that they hock. Personally, I think stitching faster then 800 spm you start to get into "diminished marginal utility" and upkeep schedule (both for the machine and the consumables) is accelerated (which I have to wonder how many actually do that). I actually don't go faster then 750 spm for hats or for flats and depending on the design, I'll go slower (this is where I like the Barudans, because I can control speed within the file itself using their native U?? files to where I don't have to babysit the machine).