Where to start?
1. Build quality seems alright, as opening it would void garanti so...
2. No need for extra power adapter/battery as it is powered by the midi-cable.
3. Filtering of allot of MIDI data can be done via the mini switches and programing it with midi data sends from your DAW or equivalent.
4. 1 in 4 out splitter/midi through.
I will use this in my synth modular environment. Some of my Midi to CV stuff can make use of different signals. Using this I can get Aftertouch, Velocity, Note, Gate and some CC values as CV and get a massive control over my sound via the keyboard (not tweaking knobs all the time).
Also an important point to make: If you got old gear with Midi from the eighties it might be well worth to filter away the extra data keyboards might send as the interface at that time was not very powerful and would choke with too much data, this lagging and making your playing sound bad and out of rhythm.
Recommended!