I love the Canon STM lenses, work great for travel, as they are quite light, decent AF speed and sharpness. I've got the "STM trinity", 10-18, 18-55, 55-250. Will e adding the 50mm F1.8 STM to it soon. What I really need though is the Tamron 150-600, the wildlife here in South Africa is amazing, and the 55-250 is just not enough reach.