Just got me a pair of Hollis F1s. Used them for 5 dives. I have to say it, these are the best fins I have ever owned. They feel slightly negative, though they are not extremely heavy for travel. The spring strap is top notch and I really like the whole build quality. I am sure these will be great fins. I am now tempted to get an M1 mask to go with my Hollis fins .