Should i Buy Quinn or Irelia?

Hello Summoners, its my first post on the Boards ever so please bear with me. I'm at Lvl 20 with 3000+ IP atm. As the title states I cant decide on whether to buy or I want to buy both but i dont know which to buy first.

I'v only played once & that was at the end of her free week i got 23/5 as her but i guess it doesn't count since it was a bot game. I kno Quinn aint a great ADC, but she's a great Top Lane Bruiser, and a Great Mid Lane Roaming Assassin. She's really fun to play and i think i might become a Quinn main (plus i might buy Phoenix Quinn).

On the other hand i like cuz she can carry games. I have never played her, but she seems interesting. she has great sustain, though she's weak early; but once she reachs lvl 6 or gets her Sheen /TriForce she powerspikes and becomes a beast. And even more she can build Tanky while still having reliably DPS. ( If i buy ill buy Aviator Irelia){{summoner:10}}

I Cant decide betwen the 2 to buy first, but atm im leaning towards Irelia, cuz she costs less and tbh i think for 6300 Ip Quinn is Overpriced (I kno shes a new champ so that's y her price is high) Irelia also seems a bit safer to use. can u guys help me with my Decision plz.

P.S: I also wanna buy too cuz he's an Untouchable OP Top Lane God