wotsupnow,

Welcome onboard
It depends who you are flying with and the airline policy, but most allow you to choose your seats. There's a topic on Self service check in / Online check in for more information. The biggest disadvantage with them is if you have luggage to check-in, you still have to use the baggage drop off desk, but great if you're hand luggage only. There's also a dedicated Manchester Airport topic.

Darren