I have flown thru LGW in J and found it fine. Had to wait until circa 3-3.5 hours before departure for the desk to open if I remember rightly. Phone skywards for details of time. Check in smooth, fast track thru security. Lounge up to the best emirates standards, well stocked and attentive staff. We were on an old 330 but it was fine apart from that. Depends on your aircraft - check emirates site for the detail on that.