I found W4R1 a surprising jump in difficulty after breezing through weeks 1-3 and was still a bit stiff today so was a bit apprehensive. I needn't have worried, I had so much left in the tank with a minute to go of the second 5 minute run that I sprinted* it I could have kept going and as I was still a couple of km from home I was tempted but no, "Stick To The Plan" I thought and went on to the 5 minute warm down.
As that left me some way from home I did have a sneaky 2 minute sprint* up to my usual "5 minute warm down" point
* "Sprint" is a relative term in this case!