I'm mixed really, I've only seen odd episodes of Underground, outside the cheesy songs though, I think it was a matter of taste. Sonic X, even in the Japanese version, has some real wallbanger moments (some elements are actually better in the dub, for example episode 57 gives some establishment on Knuckles believing in Eggman all the time, the Japanese version has a broken aesop about how it's good for the team to use him as a patsy after berating him about Eggman using him in the same manner). Also from what I've seen of Underground it had a mood similar to SatAm, ie. a balance of darkness and whimsy at the same time, in comparison to Sonic X which fluctuated uneasily between juvenile and cartoon to outright grimdark.
Having lots of characters from the games isn't necessarily valid if they aren't developed much, half the cast in Sonic X were bland as hell, at least Underground gave personality to the title character. I admit I prefer some of X's original characters (Decoe, Bocoe and Bokkun beat Sleet and Dingo as Eggman minions to me).
Both shows kinda suck with battle scenes (Sonic vs Knuckles in both cases) Voices in both are iffy (Sonia's Urkel voice vs Gamma's ET voice) though I may be inclined to say the acting was better in Underground, even if Sonia was voiced by a boy he at least acted her okay, I go back to some episodes of Sonic X and am surprised how much the voice acting has improved since then, even Pollock sounds rather forced and bland in early episodes. Also while the dialogue in both was cheesy Underground could at least reframe from using a pun or one liner in EVERY DAMN SENTENCE.
As said however this is abiding by what I've seen of Underground which isn't a lot so if these statements aren't valid feel free to correct me.
This post has been edited by E-122-Psi: 01 July 2010 - 08:07 PM