In my experience the 898 runs just fine. It's an earlyish departure on an A320 which means the daily delays haven't had a chance to build up and TIP certainly isn't a slot controlled airport. Once the aircraft makes it to TIP the turnaround is usually fairly straightforward as there really isn't very much to go wrong there, due to the fact that there really isn't very much there period. The air traffic control system at TIP is fairly rudimentary which means slot delays back to LHR sometimes don't seem to make it to ATC there which is err, cough cough, most unfortunate.