It depends on your requirements and technical skills.
If you have he expertise to add the membership functionality either as a custom feature or by properly integrating a plugin then you can use whatever you want.
If that sounds daunting then maybe look at something with a functionality in place - again this depends on what platform you want to use, complexity of membership options etc.
Bear in mind that if you plan to charge people to be members and use the site then you need an extended license which will increase the cost quite a bit for some files.