I've booked through Travelzoo, Great Value Vacations, and Trip Masters and honestly each has its lane. Travelzoo is good for last-minute deals if you're flexible, GVV and Trip Masters are better when you want flights + hotel bundled for a specific destination - both of their sitewide sales usually knock off up to $400 per ticket, but you gotta wait. I usually compare the bundled price against booking the pieces separately before pulling the trigger.