I use a set of WV-NM100 for over 3 years now.
My two requirements were: wired (not wireless!) network and e-mail capabilities.
It's not bad.Takes and e-mails pictures when somebody is at the door.
Not very fast. Pictures not very high quality. You can connect and monitor live. Zoom option.
Up to 4 cameras. So-so software. It was good when bought, today it shows its age.
Can be accessed from the internet (if ISP allows) by simply placing in DMZ and port forwarding.
Gives control over configuration and monitoring.
I accessed it from work, Mexico, Europe and India. As long as you have fast internet, it works fine.
I use dyndns.
Diogen.