hello,
I am using hikvisioneurope.net - for hikvision units, and myq-see.com for qsee.
advantege for hik... - i can see if my units/customers are online, in one page i have all units.
advantege for hik.. and qsee - they privide free dns redirector - no need for public-static-ip; - i have more easy adress to remember ( for customers ).
until now i don`t fiind disadvantage.