Logos has become a daily companion to me in my studies, and I received special profit from it during recent comprehensive exam studies. Here’s a selection of works I used to study textual criticism and New Testament introduction (these works came with Scholar’s Gold, some Theological Journal Library volumes, and the BECNT and WBC sets):
- Guthrie’s NT Introduction
- Darrel Bock’s BECNT volume on Luke
- Bill Mounce in the WBC on the Pastorals
- JETS and WTJ articles and reviews by Grant Osborne, Moisés Silva, and others
- Richard Bauckham in the WBC on Jude
- Timothy George in the NAC on Galatians
- Richard Longenecker in the WBC on Galatians
I didn’t use Guthrie as a textbook when I took NT Intro, and I was quite impressed with the level of detail he goes to. Carson and Moo (and, when I took NTI, Morris) have a fine NT Intro as well, but it was very good to check other views.
I encourage you to look at the basic Logos packages and add up the value of the books you feel you would profit from. See which package would be most worth your money.
A little note on the North and South Galatia problem: Check out ch. 7 of Silva’s Interpreting Galatians: Explorations in Exegetical Method.