Easy to call a unit rubbish if you don't have the first clue about its rules. :P
These days I'm mostly playing bugs, because someone has to play the villain. Basilisks are a genuine threat to big critters and are hard to get to grips with if they're properly hidden and supported by infantry. Wyverns are similarly difficult, but can simply be ignored a lot of the time. They're really expensive for something that is designed to mulch cheap chaff. With no AP as the save improves the Wyvern really starts to have a bad time, and there's a noticeable difference in volume of Wounds as Toughness increases, even with the reroll.
I faced two last night within a Guard list that also had Chimera Infantry Squads and three TC Russ Battle Tanks. I ignored the Wyverns the entire game, and during the game they had free rein to target my large Hormagaunt and Termagant squads. By the end of the game, with support from Guardsmen, etc, they had almost killed both 30 man squads. He wasn't even rolling that badly on them.