My car octavia VRS diesel some times while driving feels like it misses a beat now and again. Has anyone experienced this ?

More details - at what kind of revs and in which gear and is this part throttle cruising or flat out?

 

There is some strange fuel cut off mechanism to do with rapid deceleration or coming over the crest of a hill, but under normal conditions you shouldn't get flat spots.

 

If you are off boost though (below 1700 rpm) it will feel sluggish.