I agree with Bobcat that "The Word Study Greek-English New Testament" by Paul R. McReynolds is the one to buy.
It and the Kingdom Interlinear Translation, in my opinion, are the most useful of the bunch. Most of the other interlinears are of little use, compared with these two.
I disagree with Bobcat, though, on the issue of Luke 23:43: I don't think the NWT Committee was obliged to follow the comma placement of the WH Greek Text. There was no punctuation in the original manuscripts, so WH used their theological judgment on that one, and the NWT Committee did the same. It is not a matter of dishonesty, it is a matter of interpretation. It is not unusual for Bible translators to deviate from the Greek Text they follow at times. It is standard practice. In many cases they acknowledge so with footnotes or other, like the KIT did at Lu 23:43.