Great fins for those starting off spearfishing or those who just don't want to buy the expensive carbon or fiberglass blades. They have served me well as I've advanced. They're fairly stiff and give a good thrust off of minimal effort. The foot box is good quality rubber and pretty comfortable. It is extremely convenient to be able to remove the blades. Great for travel. The downside is they are pretty difficult to get back in. Takes a lot of pushing and twisting and swearing. The tracks that the blade slides into have a tendency to get folded in when you're trying to push the blade in. It makes for a pretty frustrating experience when some of the blade is in the track and other portions are out. If you don't correct it, the box will pop off. Last Mex trip, i took my fins carry-on, strapped to my backpack so i didn't have to deal putting them back together. I think you will experience this assembly difficulty with most fins with removable blades. Another downside to these fins is the tips of the tracks. They get pretty thin as they tapper down the blade and already seem to be splitting. I've had these fins for a couple years. Other than that these are great fins. If you're serious on ultimate performance look into fiberglass blades. Though with those you'll be paying around 500 just for the blades. With the plastic blades at least you don't have to worry about scratching them. Great for ab diving. With that said, I tried to find blade replacements and couldn't find them anywhere. So if they were to warp or break, you may be out of luck on replacing them.