Ah man, I really like both these bands.
Undertow is my official skiing disk (tape back in the day).
On the other hand, Tesla was one of the best half a rock shows I have ever seen. I say half because they blew the sound system. Either that or Def Leppard (headliner) was intimidated and pulled the plug. Those were my party days! I highly recommend picking up or at least listening to Mechanical Resonance, the debut album by Tesla.
Tesla gets my vote in what probably will be a losing effort. They get no respect.