Robert P. Gordon has provided us with a substantial commentary on the English text of the books of Samuel, concentrating on exegesis, but also paying attention to linguistic and textual problems. "I have not tried to "Christianize" 1 and 2 Samuel at every conceivable point. Often as I have sought to show in the brief introductory section comparison; and the only way to arrive at sensible conclusions in this matter is first to appreciate the Old Testament for its own sake- that is in its own literary, historical, cultural and theological contexts. That is principally what this commentary is about."
Gordon has written the best single-volume commentary on the books of Samuel that I've read or surveyed in depth (which include a significant number!). His exegesis is sound, his knowledge of ANE customs and texts is exemplary, and his narrative reading/literary analysis is competent. His primary issue is that this is a very short commentary: he doesn't deal with every problem or every verse. You wouldn't be wrong to think of it like a collection of notes rather than a full commentary. If you deal with that, and the problem of his publisher choosing to use footnotes rather than end-notes, and that leads room for improvement. Regardless, though, this is well worth a purchase if you're reading through the confounding books of Samuels.
(Of note, for those that care, Gordon comes from a moderately conservative stance on the volume, but interacts with multiple views therein.)
From the Old Testament Guide series, not a commentary as such, but rather discussions on key areas of the 1 & 2 Samuel. A very interesting guide that sparks thought