I watched the entirety of the WW1 series. It was quite informative for someone like me with only a basic understanding of WW1. Some of the narrative in the earlier episodes were quite repetitive but it got better as the war deepened. Also their maps also improved in the later years of the war.
I have also tried to get into the Between Wars Series but the content is disjointed and you end up all over the place. This series has a different commentator.
I also tried watching the WW2 series but couldnt get into it. Something felt off about the commentary. Not sure why.