If the flight rom BKK is late, they have in the past delayed departure of the UK bound flights. DXB is a massive airport with 3 in line interconnecting terminals. The distance from A to terminal C (thro' B) is huge , however there are trains that shuttle from one to another. I have read somewhere that (nearly) all Emirates flights are now gated at Terminal C so that should help with transfer time. Personally I would not use DXB if I wasn't an Emirates customer; firstly it's one huge shopping mall with the same shops and food outlets repeated every 100 metres , and the real pain is the wonderful smiling welcome you get from security that you have to pass through when you arrive.