Well the build quality is there and off the rail the Bosch has a very small footprint, so stability isn't good, especially when edging. Hand hold on the Bosch isnt that great imho, plus your fingers are nowhere near the on/off whereas the Festool has a handle with an easy to get to trigger switch.What makes it better than the others ? I use a 1/4 Bosch GOF600 which works well with the rails using an FC tools adaptor, which also allows me to use a Trend T10 on a track as well.
The Bosch is constant single speed, which isn't that good, especially for larger cutters(No we arent talking huge cutters) because different diameter cutters require different speeds.
But in all honesty you cannot really compare a trimming router to a versatile 1/4" router just because both have a 1/4" collet.