The delay depends more on the way of signal-transmission than on Kodi and VDR. Sometimes there is a difference from more than 100 seconds between DVB-S and IPTV.
Most of the time this is no real problem, but e.g. when watching the Europen Football Championship, it is of course annoying, if the neighbor always cheers at a goal one minute before you can see it on your TV
The fastest transmission signal-transmission has DVB-S/S2, then follows DVB-T2, DVB-C, DVB-T and on the last place IPTV.
The delay of Kodi depends on your hardware, the used software and on your configuration. Normally the delay is here rarely higher than 1-2 seconds.