Carbonite backup services literally saved all the pictures and videos of my kids from a fire. I use it personally, at church, and recommend it to my personal clients.

Button with lights

Delay switch sources, may take 2 seconds with an obvious screen blip

No preview screen

Plenty of lag in conversions

Not network accessible

Not rack mountable

Probably HDMI signals so not more than 50ft transmission

May/may not have rs232 remote

Example: J-Tech 4×4 Switcher

may/may not have buttons

Probably no preview screen

Slight delay in switching sources

Some lag in conversions, but not much

Network accessible

HDMI converted to ethernet for long transmission

Probably rack mountable

may/may not have rs232

Example: J-Tech Digital ProAV Network Matrix Switch

SDI connections so long transmission, especially if using some sort of fiber converter

Physical buttons

has preview screen

Almost no lag because of analog signals

Network accessible

Definitely rack mountable

Rs232 control for sure

Example: Blackmagic smart videohub