i recommend the pantabangan route. mostly well paved roads. the only hassles are the approaches to the various bridges which last year were unpaved. kaya ng sedan, just watch out for those rocks so choose your path well if your car is heavily loaded.

dun sa mga "damn dam" na sabi ni sirkosero, ONE lane dun. bubusina ka muna or pag may nakita kang kasalubong tabi ka muna dun sa stretch na kasya ang 2 vehicles and let the one who is first to enter the 1 lane stretch pass.

long but fast: nlex-sctex-exit sctex at tarlac city-turn right to la paz and zaragoza. there is a by-pass road after zaragoza that by-passes cabanatuan city (grabe traffic last year in cabanatuan due to a bridge under construction). sa may carmen na yata if i remember right. may signs naman so watch out for it after zaragoza. turn left ka dun and turn left at felipe vergara hiway. turn left again at pan philippine hiway then turn right at the Y intersection that is already the hiway going to pantabangan and straight all the way to baler.

short but plenty of traffic: exit nlex at sta rita and follow the pan philippine hiway all the way to cabanatuan. sus grabe traffic dyan. sa san ildefonso lang ako nagpunta inabot ako 2-1/2 hours. in 2-1/2 hours via the la paz route you can be in cabanatuan already.