Well hello! That's my first guide on MF, i hope you like it.

I LOVE QUINN! I couldn't rest without finding a good set for her, and my playstyle.
I am a "crazy" player, fully offensive and i hate to hold back. So, for my guide, it wouldn't be different. I will not speak about her's pros or cons, because that's written all over the MF, so LET'S GET TO WORK!

I take IGNITE and FLASH for summoner's spells. FLASH for the lack of a gap closer and IGNITE to avoid tower diving in the laning phase. And of course, IGNITE, to do more damage and guarantee hard kills.

That's a full offense build. And YES, there's 2 IE. It seems a strange build, but it gives you: about 1.90 (2.10 with H. Senses effect) atack speed, about 350 atack damage, 250% of critical damage, and 100% OF CRITICAL CHANCE! In the end, you will be dealing about 800 damage with a single hit, and about (or more than) 1000 damage with Harrier's effect.
It do not give you mobility or sustain, you'll have to be extra careful and focused. If you do, you'll finish your enemies in the speed of light, even tanks. And to compensate the lack of sustain, you'll have TONS of life steal.
PS.: Start with DORAN'S BLADE, and sell it after, of course...
PS².: If you die or recall, buy something always.
PS³.: At the laning phase, after buying a core item, i buy health pots if i got some money left.

About the skill tree, i max Blinding Assault first because it always give me kills when i'm outranged, and it deals more damage.
Vault is the core skill for Quinn due to Harrier's effect, but you don't need to max it to get the mark.
I use H. Senses when i think that someone's hiding near, and when i'm chasing that someone in the jungle (don't try to gank me... LOL), so it's a "neutral skill" and i max it last...
For the ult, of course i go the common way.
PS.: I love ganking from brushes with Tag Team actvated, especially others ADCs. They do not have time to react, and it's always "OMG" "WAT" "WTF" after it. So it's a lot of FUN! LOL

I'm taking full offense and the movement speed. There will be 2 points without "destiny", so i put them on SUMMONER'S WRATH and SUMMONER'S INSIGHT. But i think you can do whatever you want with them...

Full offense too. You'll rely on careful observation and attention to avoid hits and stay in one piece. And, OF COURSE, a good support.
I take flat damage instead of armor penetration to do much more harass to the enemy ADC and even more to the support, that do not have armor runes major times...
Atack speed gliphs, because, even with the effect of H. Senses, i think she's slow and don't have damage enough on atacks without Harrier's effect. So it's pretty good to have'em.

About team work, it's written all over this guide "YOU NEED A HEALER!!!". And yes, she does. Sometimes i play with a support Blitzcrank, but that's a risky move.
So i think Soraka's a good support, healing and filling your mana, so you can harass without stopping.
I like Sona too. She can give you armor, magic resistance, she can heal, give you atack speed, stun, but Soraka's better i think....
But there's one support that i think it's the best: TARIC. He/She (:P LOL) can heal you, stun enemies, give you armor, and, ABOVE ALL, TAKE THE HITS INSTEAD OF YOU! Haha, that sounds pretty bad, but if you have a good support Taric, the bot lane is yours.
It's always good to have synch with your team mate. I, personally, like to make a lot of burst and fall back, and, being a synchronized duo, it goes pretty well.