D.A. Carson's 'New Testament Commentary Survey' (5th edition 2001) lists 'best buys' for single Romans commentaries as;
D.J. Moo in NIC
T.Schreiner
C.E.B. Cranfield (for advanced students)
A. Nygren
The earlier version of 1993 lists best buys as;
Cranfield
Moo (wait for NIC)
F.F. Bruce
C.K. Barrett
A. Nygren
On Nygren he says, " One of the best for the theological flow of thought in Romans is the work of Anders Nygren (Fortress 1949) Everyone who can do so who can do so should grasp his general introductory remarks on pages 16-26. Unfortunately, however, the book is inadequate as a verse-by-verse commentary."
Carson covers all of the authors of commentaries on Romans with at least a gloss. Haldane gets an honorable mention, as well as Hodge. On John Murray, "will guide you stolidly with the heavy tread of the proverbial village policeman (although with more theology; and note especially the useful appendices and notes)"
On MLJ; "Lloyd-Jones is probably not the model most preachers should imitate, but the set is easy to read, and Lloyd-Jones sometimes offers material one is hard pressed to find elsewhere--in addition to the wealth of his practical application of Scripture."