we bought one. waiting for delivery.
i will tell you exactly where i think the problems will arise.
the door from disc chamber to mill area is magnetic....dust will go in and out for sure. The vacuum is only connected to the milling side. The screw rails are exposed (at least at IDS, maybe won't be for production) in the disc chamber - again, easy to gunk up over time.
beyond that, should be pretty much the same and as reliable as the 50DWX and 51DWX. We currently have 4x 51 DWX running.
We are hoping mill box will let us Q up and help us diversify as we get into more and more different puck types.
We have sold many hundreds of Roland mills. Never taken one back due to customer dissatisfaction and Roland is the best when t comes to support. The DWX-50 was likely the mill that made milling in labs mainstream. The 50 did have a lot of plastic. The new DWX-51D is metal. In addition, they moved from wire drive system to the more conventional ball screws in the 51. The 50 had the rails exposed inside the mill chamber. The 51 has two compartments, the mill chamber and a second, in the back to keep the components clean. In addition, the suction for the mill keeps a negative air pressure inside the mill chamber. This makes for air moving into the mill from all cracks or seams in the door which reduces or eliminates dust from getting out of the mill during milling. Other improvements over the 50:
1. Users can replace the spindle when needed. No need to ship your mill
2. The spindle is inexpensive, under $2K. We have had several last 5k hours.
3. A funnel-shaped mill chamber that enhances dust collection.
4. The 51 comes with an ionizer to eliminate static when milling PMMA, resulting in a cleaner mill.
5. New clamping system that will allow end milling for large Izir type cases.
You will not go wrong with a Roland. it is priced affordably and designed to provide years of trouble free milling.
I checked out the mills at CAP last week and found that our oldest mill has been running for over 12K hours, resulting in the production of 36,000 units. I did this as Sam and I did a webinar on the 51 & 52DC (disc changer). You can view it here.
http://cap-us.com/events/webinars/