The 340R, 540Rv3 and 640R do not perform any kind of video conversion, so a Composite input will only come out as Composite, an SVHS input will only come out as SVHS, a Component input will only come out as Component, and an HDMI input will only come out as HDMI.
The 650R, will perform analogue to HDMI video conversion, thus allowing you to run just one cable to your monitor.
The 551R, 651R and 751R will transcode analogue material to HDMI and additionally offer upscaling as well.