Round Menorahs

The Terumas Ha-Deshen (105) discusses whether a round menorah is acceptable for use. He answers that if the branches are insufficiently separate then there is a problem that the flames may join and the entire menorah becomes a "torch". However, if each branch is separate then there is no problem of a "torch" and the menorah is entirely acceptable. The Rema (Shulchan Arukh, Orach Chaim 671:4) rules like the Terumas Ha-Deshen.

However, the Maharshal disagrees with the Terumas Ha-Deshen and Rema, and rules in a responsum (no. 85), while agreeing that such a menorah would be technically permissible, that it is not preferable because it is not optimal (mehudar). This ruling of the Maharshal is widely quoted by commentators, including Magen Avraham (671:4), Taz (671:2), Chayei Adam (154:10), Mishnah Berurah (671, Bi'ur Halakah sv. u-mutar), Aruch Ha-Shulkhan (671:14) and Kaf Ha-Chaim (671:31).

Interestingly, the Pri Chadash (671) also disagrees with the Maharshal and says that round menorahs are mehudar and that great sages have used them. The Pri Chadash frequently does not get respect (see the introduction to Bekhor Shor) and this ruling is not quoted by later authorities.