Quitting Without Formal Written Offer

There’s been many topics on this, I’m well aware of that, but I was curious about people’s thoughts on my situation. I am an associate looking to change career paths (IB>AM) and cities. I know this doesn’t sound the sexiest to all of you but I can get comparable all-in pay and work 40 hours a week or less in a city I want to live in.

The company has provided me a verbal offer and wants me to start as soon as possible and was part of the reason they wanted to hire me. Like most junior bankers I have a two week notice period from when I give formal notice after passing background check etc. I am debating giving notice to my company now before any written offer. The work situation is crappy and about to be terribly busy and the following reasons are why I don’t think it is a problem:

• I went through 5 interviews and it seems unlikely to sink those resources without following through and hiring me. The role is relatively senior

• I have passed multiple background checks for banks/FINRA so I don’t think that would be a problem

• most importantly I would kill for an additional week or two off to go on vacation and do absolutely nothing, especially if my current employer makes me sit out my two weeks which I think there’s a 60% chance they may. And finally I don’t need the paycheck I’d miss out on.

Thoughts? What am I missing