It does a really nice job planning travel for 1, but doesn't handle multiples well at all. It's better to specify times, locations, activities, and budget for the party on location, while specifying the per person budget for all travel. Make sure you craft your prompt appropriately. But I really like the suggestions of locations and activities presented when I said "Europe for X days starting in City 1". It returned results in NLD, SPA, FRA, and ROM using public ground transportation.