Hi Sylphyo Friends, this is my configuration with mini UPS and Soundbank for the front pocket, works fine, sounds fine and I never had problems with it.
I did paid 350 Euro for the Ketron and 50 for the UPS. It can be charged in the car.
And there is still place for a clear sounding soundbar in the bag.
The Ketron has 290 Orchestral Sounds, 292 GM sounds and also Efects:
Multi DSP effects
If somebody knows how I can use them please write me.