Qantas flights: How does Dubai compare with Singapore as a transit point to London?

Another vote for SIN - IMHO much nicer overall. DXB is OK if one flying directly to LHR (i.e. no changing of plane), but could be true nightmare if one trying to connect to other European cities - either lond layover or incredibly inconvenient arriving/departure time. Also as been pointed from sheer prospective of flying effectiveness it is always better to fly as perpendicular to Equator as possible (i.e. SIN win here as well).