Try one out on a spare piece of fabric first. I've recently had nightmares trying to find snaps that could be properly installed and snap together easily and in one case be able to be pulled apart again once closed. I gave up and used buttons. I didn't try any pearl ones though.
Also, if you do get them, make sure the fixing tool comes too. I bought one lot and had to get the tool separately when I found they didn't come with one.