Back in 2006 when I began using and buying Festools I already owned many sanders.
My first Festool sander was an RO 150 and my second an ETS 150/3. What I did not already own was any sort of delta-pad sander with a pointed end. The weekend after I bouth the two 150mm sanders I purchased a Deltex DX93. I have enjoyed using it ever since early 2006.
All of my work starts with new wood, so removing old finish is not my problem. Hardly ever do I use a grit coarser than 100. Something I love about the DX93 is that it is only 150w, meaning I am less likely to over-sand. When I build cabinets nearly always the portion of plywood visible is factory pre-finished, so that never gets sanded. Much of the time anything needing sanded is sanded before assembly, so I can and do work with large round sanders.
However, face frames, edging, doors and drawer fronts I make from solid hardwood. I mill that in house. Everyone working for me takes pride in the way we set jointer, planer and molder knives, yet often to bring out the beauty of that hardwood some sanding is needed. Until the RO 90 DX came along I personally used my DX93 for sanding rails and stiles of frames.
Please do not get me wrong: the RO 90 DX is a marvelous tool. With a round hard pad I can beautify frames faster than with a DX 93 and spend less on abrasives. All but one of the master cabinet makers working for me prefers the RO 90 DX in delta mode over the DX93. Two of us still prefer the DX93. As a matter of fact, just a week ago I bought my third new DX93. The lack of a Plug-It cord has never caused me any grief. I also have no problem with the oval dust collection port.