I played Flygon ex PK with Delcatty for a while (and with Noctowl, I called it Boostcatty as you might recall) but I was quite unhappy about the low speed of it all. Apart from that, I don't think Flygon ex PK would be a suitable tech in that many situations (even though it can reduce a Revenging Machamp to 0 ftw) but if you really like it that much, I won't stop you. Still, I think that Bronzong is a better tech in Queencatty, gives you an extra (weak version of an) Energy Drawer if you already got a pile full of Pokes, and otherwise it can discard one Poke each turn.