Originally Posted by
Short Final
I would say its a bit risky yes.
Assuming you want to reach T5 by 2000 ! Assuming your inbound doesn't arrive late, you are not held up at immigrations or customs you're unlikely to be leaving LGW much before 1830-1900 anyway !
I am arriving from JER- so at least I manage to skip the whole customs/immigration problem. I might book a car from LGW-LHR instead of the national express bus to speed it up a bit!