These skins are very easy to replace. The remo djembes I have bought each came with a key for loosening the head (you might need to give the old skin/head a strong push from inside the drum). The new heads just sit on the drum and you will need to hook over and tighten each of the bolts evenly. This takes a couple of minutes, compared to the hours (over a period of days) that traditional djembe reheading takes.
As with any synthetic skin, the sound is tinnier than you will find on a traditional djembe. Because I work with large groups of beginners, it made sense to choose drums with easily replaceable heads even though I would loose some sound quality.
The surface of these drum heads does begin to peel away over time. When the edges begin to scuff, people can't resist peeling off a bit more. Also, sometimes large blisters have appeared between the coating and the plastic/mylar of the drum head. Although this doesn't affect the sound, I would prefer a coating that was more hardwearing. If you are buying this for personal use, I expect it will be suitable. My drums see a lot of action (people wearing rings, using mallets, kids picking at bits), so you might not have the same worries, just be sure to keep the edges safe from scuffing.