I like Aiphone and their trouble free solutions for access control. The Aiphone JKS-1AEDV is a simple boxed set comprising of a Door Station and Master Monitor Station with memory, power supply and some cable. This set can accommodate one additional sub-monitor station (JK-1MD)
The Aiphone JKS-IPEV is the same boxed set except the IP adapter (JKW-IP) takes the place of the additional monitor station but it does offer full door control from up to ten PC's.
I have 2 customers who want a standalone IP based system with 2 interior monitors. Suggestions welcome please. Thank you in advance!