I only thought that both guys were counterparts because they took off their shirts in front of their girls. However, the fiasco is different, because Trent helped Gwen win the season, while Alejandro only did it to manipulate women and get them eliminated on purpose.
Despite the fact that I brought the fabricated comparison up, Alejandro and Trent are different, since:
Trent: Nice, clever, strategic, caring, kind, benevolent, selfless, innocent
Alejandro: Wicked, rude, vain, mean, manipulative
However, this should've ended when Heather got eliminated in TDAS, courtesy of Alejandro