I've also used the Word Study Greek-English New Testament, but it's large and printed in all caps. I didn't like it. Biblehub's interlinear was very useful, but is online only. I suppose it's a bit of a niche question, since it didn't take long for me to graduate to UBS Reader's Edition.For a printed interlinear, the most useful that I know of is produced by Jehovah's Witnesses. It's called the "Kingdom Interlinear" and you should be able to order a copy for free if you are willing to ask one of the people standing next to the displays at BART stops, etc. They stick "Jehovah" in for κυρίος in the running English translation -- fine in Hebrew, wrongheaded in Greek -- for theological reasons. But other than that, I can't find too many faults. The Greek text is plain old Wescott and Hort.
The method I suggested to my friend was what I started off with: use the interlinear + translation to learn a block of text, and then review entirely with the Greek text (no English notes).