I have a pair of Mares X-Streams, and used them for a short while, including a trip to Kauai. They were nice lightweight fins for travel, and had reasonably good forward propulsion. However they lack good sidewalls for more precision maneuvers and anti-silting fin kicks. Specifically, they don't do as well for helicopter turns or back kick as more traditional blade fins.
The Mares Excel+, which I have, and Avanti Quatro, which I used recently for cave diving in Mexico, are both more versatile fins. I often travel with my Excel+ fins for open water diving where I may encounter current. I think their propulsion is superior to the X-Streams. They are a bit longer than some other models, but I have a bag they fit in.
My preferred fins for cave or wreck diving are the Dive Rites. Back in early 2015, when I showed up in Thailand for a Full Cave course, all the instructors and most of the students at the shop had Dive Rites. They are good stiff fins with the right amount of 'snap' to their action. I can stop, back and turn on a dime with these in restricted spaces.