Where is the best place to book your flight??
If getting to Gatwick isn"t an issue and you are only going to Vegas, then I would strongly recommend flying direct with Virgin. It will most likely be a few pounds dearer, but [IMO] the advantages far outway the extra cost.
No connecting flights to miss, because your first flight was delayed by an hour... no hanging around for 4 hours in some departure lounge waiting for a connecting flight that"s been delayed... you can sit in a $1/$2 NL cash game for a couple of hours and win enough to cover the extra cost before those flying indirect even get there!
The international terminal at McCarran only has a handful of arrivals each day, none of which arrive anywhere near the same time as the Virgin flight... therefore, no delays at immigration / baggage carousels / taxi line. The domestic terminal has flights landing every 5 mins, no immigration (you did that somewhere else) but there can be long waits for bags and a long taxi line.
You arrive in the afternoon, no long queues at the hotel check-in... which can happen in the evening (especially Friday). And you will be there in time for the 7.00pm tourney at Ceasars, to be followed by the 2.00am at Binions and the 9.00am at the Rio!! (Well that"s what we did last time.
)