The first episode, The Great War, is very strong, with excellent soundscapes of the battlefields and a good firm introduction of Molly as a character who is more of a time-traveller than she realises. It also introduces Peter Egan and Toby Jones as the mysterious figures Straxus, the Time Lord agent, and Kotris, in league with the Daleks. Jones is particularly good, I think.
The second episode, Fugitives, felt less coherent to me. Part of it is set in the early 1970s at a London scientific institute, but there are also excursions to Dunkirk in 1940, and a planet with intelligent but incomprehensible dolphins.
The third episode, Tangled Web, is partly set in Ireland as the Doctor attempts to visit Molly's childhood, but mainly set on what appears to be a peaceful post-conflict Skaro. By this stage I had pretty much lost my grasp of the overall plot, but I just loved the scenes of the Doctor dealing with a world where war with the Daleks was a thing of the past, and the story did not fail to deliver.
Finally, X and the Daleks does actually resolve a lot of the plot loose ends, making it clear who was working with the pepperpots and why, and how this affects the internal politics of the Time Lords and the Doctor's relationship with them.
Bradley's performance as Molly really lifts the whole thing and gives McGann something very different to play off, so everyone is a winner. As noted above, I felt that the second episode was weaker, but the rest is good and the second half delivers on a strong start. You can get it here.