Qwilfish and Exeggutor are the best users of Swift Swim and Chlorophyll in Ubers respectively. The amount of damage that Qwilfish does is impressive, allowing it to revenge Latias, Latios, Mewtwo, and even stuff like Kyogre if it isn't running a ton of Defense. Getting choice-locked into a Poison / Ghost move can suck, but you are mainly there to clean late game when these things have been removed or force CM users out. I don't like Exeggutor quite as much, but it does have a very powerful Solarbeam and Explosion that can be threatening, especially late in a match. I don't think mm2 got the best impression of Exeggutor when it failed to check his sub-salac SD Groudon in a friendlies match, but to be fair that was partially my fault for testing a slower spread on Exeggutor and not making a safer play with Snorlax.