Let's be honest, nobody ever orders from Gigi's for the food. You order Gigi's because you're 9 beers into a bender or 3 hours into a graveyard shift and nothing's open and the idea of a 7-11 hot dog makes you lose your appetite. The fine proprietors of Gigi's are of course aware of this situation and have come up with a clever scheme of delivering nearly anywhere and charging you literally all your money. Bearing this in mind when you finally throw up your hands and order from them at some god-forsaken hour will save you a great deal of frustration.
The food is nothing to write home about: somewhere between the cheese apparently sourced from a chemical factory and dough that's so fermented you might not want to consider driving for the next hour or so, you're in for a greasy experience barely a notch above a frozen pizza. Should you decide to engage in a number of complex wire transfers with your Swiss bank account and spring for the Greek food, you're in for a slightly better experience where passable roast lamb meets un-fuckupable roasted potatoes and tzatziki that would taste good on anything.
The service? Don't expect any. Gigi's is there to serve your 2am drunkhungrys, not give you a smiling experience. Sometimes things go really bad though, like they take and never deliver your order. Should this happen, make sure you call back before half an hour before closing time, or they will refuse to pick up the phone and you'll have to fend for yourself. You'll curse them, rage, and promise to never order from them again...untill it's 2am and you're hungry again.
All in all, if you manage your expectations, Gigis might just save your evening with edible pizza delivered right to your doorstep, which is more than most chains in this city are willing to do.