The Seminar voted all three accounts gray, but the commentary in [The Acts of Jesus] (p. 55) notes that "the Fellows were fairly evenly divided on whether Jesus underwent a period of testing in the wilderness such as Mark depicts here. The weighted average fell just below the line separating pink and gray."
Samuel T. Lachs
Lachs [Rabbinic Commentary on the New Testament], (50):
The theme that a hero or holy man was to be tested before his career began or before his mission was undertaken is commonplace in the literature of antiquity. Rabbinic homilies on this theme are often based on Ps. 11.5, The Lord tests the righteous, not the wicked. The most notable example of this testing in Jewish tradition is Abraham, of whom it is stated, "With ten trials our father Abraham was tried, and he withstood them all to make known how great was the love of Abraham our father."
Lüdemann [Jesus], (10) dismisses the tradition as unhistorical:
The tradition is present only in rudimentary form (cf. by contrast the tradition in Q: Matt. 4.1-11/Luke 4.1-13) and the details can no longer be reconstructed. Perhaps it seeks to depict Jesus as a righteous man, a new Adam (cf. Rom. 5.12-21; I Cor. 15:45-49), who embodies the righteous son of God.