I have used DTS for awhile and same time it's good finish sander and I'm not 100% happy with it.
Main reason for unhappiness is vibration. It vibrates only little, but too much. This causes fatigue and tingle to my arms and fingers after longer sanding time. Other than that it performs well. Machine has been used (or run) for 2 - 3 hours, so the initial break-in has been done.
Here are some findings
Fine sanding
DTS is intended for this. Excellent results. DTS is for corners, edges, details and smaller areas. Random orbit sander for larger areas.
This easily removes machine marks with Granat 120 (for saw burns perhaps 80 is better).
Coarse sanding
DTS is capable to strip paint easily with Cristal, so it can be used for cornes or smaller areas. Of course 125 mm random orbit sander is more powerful and faster especially for large, flat surfaces. This is easy to use, fast enough in corners and fast on edges.
I tested Bosch GEX 125 with average quality 60 grit paper and DTS 400 with Cristal 60 on painted birch table top. GEX 125 was much faster and obvious choice, but DTS did well especially on edges or in smaller areas. Cristal last longer.
Learning curve. I found some odd scratches after sanding with lower grits (relative matter), they came easily when moving DTS across the grain.
Is this something what happens to you too?
Those marks shows under varnish/lacquer.
I sanded surface again, carefully with the grain, before going higher grit.
Also I couldn't make it float all the time, it just suddenly stops and creates some marks.
Suction. With CT at full, DTS stays in place on vertical plywood.
Use lowest setting. I found Festool adapter (for reducing suction) very practical. Except that adapter does have even surface and hose drops off easily. (DTS has those "rings".)
Dust control. Very good. Good even when sanding narrow pieces.
So, I need to use it more. To learn how it should be used and to decrease (hopefully) that vibration.
DTS is lightweight, easier handle than my GEX 125 which wobbles and wanders over surface.
Machine is intended for finishing. It can do some harder work too. In it's limits.
Vesa