The roads to the North are very a-OK especially Ilocos Norte. Ilocos Sur isn't as nice but it's still quite good. I've been going to Pagudpud basically every year since 2006 and save for the occasional stretches of paving/repaving work, the roads are a joy to drive on. My only gripe has always been the tricycles on the National Highway (inside towns are understandable) who have become worse as the years have gone by. These remind me of the talangka who impedes the progress of others.
we made a trip to Pagudpud last march and i must say the roads are above average for roads in Luzon, and in some places even very good. the only "unpaved" portions we encountered was some stretches somewhere near Bangui where some repaving was ongoing. but that was last march so i think by this time the road repairs should be finished already.
we left QC at 3:20 am and reached blue lagoon in Pagudpud at 1:10pm. the trip to Pagudpud took a little less than 9 hours, not including stops for breakfast and 1 stop topping up the diesel tank. but i think that was only because i was able to cover the stretch from QC to Candon, Ilocos Sur (where we had breakfast) before the tricycles were out on the roads. had we taken a later time then 12 hours would be par due to the traffic. also i took the right turn after exiting SCTEX at Tarlac and followed the "alternate route to baguio" signs instead of sticking to MacArthur highway and rejoined MacArthur only before Rosales. if you will be making the trip during daytime i suggest you use this route to escape the tricycles and jeepneys who "own" MacArthur highway during daytime until late at night.
tip: fuel costs less there than in the metro so fill up your tank only such that you'll have an almost empty tank when you reach Ilocos Norte.