Don Carson, in his survey of New Testament Commentaries, notes that of the making of commentaries on Romans, there is no end. Here then, is a short list of my favourite evangelical works beginning with technical/exegetical commentaries to more homilectical/devotional works:

Thomas Schreiner. Romans, BECNT. 1998.
This is probably my top pick for a technical commentary. Schreiner's work combines all the best elements: it is recent, the scholarship is first class, the interaction with other scholars is fair and plentiful, the style is concise yet readable, and his theology stands in the traditional evangelical stream. He is particularly good at explaining the logical flow through Romans - a tricky task these days when one considers the size of modern technical commentaries (this commentary runs to nearly 1000 pages).

Douglas Moo. Epistle to the Romans, NICNT. 1996.
Moo expanded his earlier Wycliffe Exegetical commentary into this highly acclaimed 1000+ page entry in the NICNT series. Occasionally the writing style is a little heavy but perseverance is well rewarded for Moo is an outstanding interpreter. Particularly commendable is Moo's assessment and critique of the New Perspective. This is a worthy volume for the serious Bible student, and not to be missed.

James Edwards. Romans NIBC. 1992.
There are plenty of excellent medium sized commentaries but for a handy sized work that assumes no Greek, my preference is this straightforward volume by Edwards. He makes good use of the space limitations of the NIBC series, judiciously picking out the key issues and explaining difficult passages with impressive clarity. It is one of the best commentaries in the occasionally disappointing NIBC range.

DM Lloyd-Jones. Exposition of Romans (14 volumes). 1971-2004
Martyn Lloyd-Jones retired before completing his sermons on Romans so this series of transcripts ends prematurely at Rom. 14:17. Nevertheless, this mammoth work is a classic and a must-read for pastors. Lloyd-Jones' method entailed preaching systematically through Romans approximately a verse at a time, leaving no stone unturned and ensuring his audience left with a clear thought-provoking message.

James Montgomery Boice. Romans. An Expositional Commentary (4 volumes). 1995

Another outstanding expositional commentary. As with Lloyd-Jones, these are sermon transcripts but with considerable theological detail. Unlike Lloyd-Jones, Boice covered several verses at a time, making these sermons more useful when studying extended passages. The series is thus smaller than Lloyd-Jones' effort but at nearly 2000 pages, it remains a comprehensive expository commentary. Particularly praiseworthy is Boice's judgment on the inclusion or exclusion of technical exegetical material.

John Stott. The Message of Romans, BST. 1994
The Bible Speaks Today series is rightly regarded as one of the best evangelical expository commentaries. This effort by Stott is typically helpful although much smaller than Boice and Lloyd-Jones at about 400 pages. The smaller size means Stott focuses on key themes, a task he achieves with immense skill, making this commentary ideal for small group leaders or preachers preparing messages on larger sections on Romans. Interestingly, Stott has changed his mind on the infamous Romans 7 debate. His earlier commentary, Men Made New (Rom 5-8), identified the description as a normal born again believer. In this commentary, Stott
adopts the view that Romans 7 reflects a weak, immature Christian.