There's usually a constant stream of DW RAS's on Ebay, along with spares like bearings and switches. I bought a 1251 a few years and and have no regrets about my purchase. It came with a variety of attachments thrown it - dado set, drum sander, disk sander and small router bracket. I have no regrets about this purchase and would go down the same route to get a replacement if the need arose. The only thing I would look out for is one with a longer arm (1551 or 1751).
The Eumenia looks interesting - I remeber John Revel raving about it when he set up his workshop (Sky real Time). However, when he made stuff I never saw him using it. I don't think this is designed to be used with a dado set but uses a wobble washer that menatmna nicely describes as ""WankNutts" in Eumenian Austrian".
RAS's require quite a lot of set up to get everything straight and square and need to be regularly checked.
Misterfish