Cripes, you can lose half an hour before you even leave the UK in the blink of an eye: ATC slot/baggage offload/etc etc....so then you're sat there chewing finger nails ( baggersup's point) then you've got the unforecast headwinds, followed by the queue at immigration ( and there's 7 of you to herd through).
In an ideal world you might just make it but I'd never plan a 1 hour 25 min transit anywhere - me thinks your travel agent is very sensible - but it's down to you - do you feel lucky
