Reddit mentions of The Bhagavad Gita: Twenty-fifth–Anniversary Edition (Excelsior Editions)

The Bhagavd Gita as it is, is the most popular translation, though I have never read it.

I suggest going for Winthrop Sargeant's translation if you want the text without commentary.

If you want one with commentary, you can buy a translation of Sri Shankaracharya's commentary made by Swami Gambhirananda. Take note that the translation is technical and thus can be difficult to read.

Also if you want independent commentary, the ones by Swami Nikhilananda or by Swami Chinmayananda are well translated and provide illuminating commentary even for beginners.

And lastly, I have been meaning to buy this one when I get the money, there has been a recent translation of Sri Abhinavagupta's commentary on the Gita.

What Smith says is largely correct, apart from the polytheism part, which as I said, I have not found.

I'd personally recommend the translation by Winthrop Sargeant. There are two editions with differing prices based on content. The deluxe edition has a foreword by the above mentioned Smith, while the cheaper edition has only the text, translation and translator's introduction.

I strongly recommend the Bhagavad Gita translated by Winthrop Sargeant. He gives the Sanskrit verse, a word-by-word breakdown, and an accurate translation with no commentary.

https://www.amazon.com/dp/1438428421/