Michael Joseph at "Evangelical Catholicism" has an interesting poll going on which of these five is the best modern interpreter of Aquinas: Gilson, Maritain, McInerny, Pieper, and Stump. I voted for Gilson, who seems to be winning. I would say Stump has made a promising start, but the thought of The Man From Aquino is quite vast, and there's a lot of ground she's only brushed up against; we'll have to see how things go over the next few decades. I like McInerny and Pieper, and there's no question that they've contributed an immense amount to Thomas scholarship; but I don't think they're in the same league as Gilson. Maritain is certainly a giant, but his thing was always application rather than interpretation, where he largely just followed the Second Wavers (admittedly not slavishly). Gilson's The Christian Philosophy of Saint Thomas Aquinas is still the best introduction to Aquinas you can get your hands on; and many of his other works on the Common Doctor are equally classic.
I'm also a bit biased, perhaps. People forget that Gilson started in early modern philosophy, and became obsessed with scholasticism while studying Descartes.