Do not book with Explore Trip. This is barely a step above an outright scam. They issue you fake/temporary ticket numbers that get "exchanged" with the airline - the trick is, that exchange often means your flight details are completely changed (different **earlier** departure times, flight numbers, reservation #'s, etc.) and they don't inform you about these differences. If you call their customer support line, the customer support staff is not able to even look up the new details for you - they send you to the airline's customer support, who are completely confused because you have, essentially, a fake ticket/record locator.
In a single trip booked via Explore Trip, I missed a flight on the way out (because it had been rebooked to a different flight #, 2 hours earlier, without telling me) and now I am up at 3 am with Alaska & Virgin America customer support trying to sort out my return flight tomorrow because - get this - NO TICKET EXISTS NOW.
Do not book with these people. Sidenote: based on my experience and several other reviews here, it would seem that this company is also buying good reviews for themselves (see all of the 5 star reviews here, which seem to name a specific person - first name only). Be warned.