He was no Spike Spiegel at all to me. That character (all of them really) was very clearly developed and Cho hit very few of the marks. Spike's a super laid back, disinterested, slacker... unless it's about Julia or Vicious, you don't really get a rise out of him.
I don't think Cho was unwatchable, but it wasn't Spike.
Vicious though, that dude was pretty much unwatchable. So terrible.
Jet and Faye by contrast, were almost spot-on personality wise.

--
"You can't beat white people. You can only knock them out."

"There is only one god and his name is death. And there is only one thing we say to death: not today."