This begs the question: What makes a translation "good"? Some would say word-for-word accuracy. Others would say low difficulty in reading and understanding. Easy to read usually means that accuracy has to be compromised. I would say that for most people, the "ideal" translation is one that is the balance of these two features (which is why I suspect that the NIV is so popular). For people who struggle with reading, an easy to read translation, the NCV or the NIrV might be best. For people who are strong readers and who are very detailed oriented, a very accurate version like NASB might be ideal. But, realistically, most people will find the best translations are those that best balance accuracy with readability. But, it really i a subjective question.
The only translations that I would say are just not good are those that are heavily paraphrased, such as The Message, NLT, Amp, TLB, and so forth. These are the ones that I think Christians most need to be careful of. But, even these are fine if they are treated as what they are: paraphrases of the Bible, rather than as the Bible per se.