Well if you think its not fit for purpose then they sell a very simular Bosch one hear
https://www.wickes.co.uk/Bosch-IXO-3-6V-1-5Ah-Li-ion-Cordless-Screwdriver/p/145296
Do you think that will remove stubbon screws or do you think its the same only will last longer?
If not that then what about...