As always, I think shorter is much better. Even if spying did/does occur, who really cares? And, if memory serves me correctly, the reason for the switch wasn't spying, it was the fact that some guys were upset about people switching sides to end an overwhelming side's abuse of a weak side- that is, they switched to high side to force the reset. Some guys were really pissed they couldn't preserve easy vultching, or that they couldn't just "own".
"What are you doing, Kieren?!"
"I'm flying the goon into the base."
"Why? If we get that field, we reset!"
"Yes, I know."
"Don't do that! We worked for a whole afternoon to get the fields where they are!!"
"What's the point? Are you going to keep it this way forever?"
"Muahahaha!"
Anyone else remember the events? Hitech happened to be in the arena shortly after one of these "episodes" and people screamed "set the time limit up!" He said "24 hours long enough?" The crowd said "Yes!" and here we are a year later.