I use both MAN & LGW several times a month and a lot depends on the day you hit MAN, but as an object lesson in how to handle security LGW does it far better IMHO
However the infrastructure issues differ "the worst for MAG for sure" .
North Terminal was designed for common usage in the first place and has plenty of space to accommodate post 9/11 style security.
South Terminal has had oodles of cash spent by GIP and again had plenty of space for extended security
Manchester on the other hand has T3 a terminal designed for primarily one carrier domestic services and with reference to a future Schengen membership "that never happened" for regional flights only so no effective security hall was even envisioned !
Rump of T1 is so over stretched today it simply is unfit for propose .
Whilst T2 was designed for a time when the value of quick kerb/airside was in vogue so again lack of space for those post 9/11 security lines we all now have to live with.
Within these existing infrastructure limitations and government dictates on security and border control Manchester Airport is in a rock and hard place right now.
Its an airport thats' evolved from being primarily a tourist departure point for the Med to having flights arrive from some of the riskiest places on the planet at the moment such as Libya, Egypt and Pakistan.
Whilst runway capacity is nowhere near used - Its got a operating limit of over 320,000 annual movement and handles around 180,000 at the moment.
The Terminal capacity is notionally about 30 -32 million mark,however Manchester is among the most variable in Europe with peak flows at times already close to capacity.
Little wonder it records some of the worst onetime dispatch figures either .
To some extent MAG and its customer airlines need to re-think Terminal usage as a matter of urgency.
Its certain they will have to if/when the proposed T1/T3 redevelopment is moved forward anyway.