I do not know how old your child is. I have both but would not recommend either for a young child. I am currently teaching my 3rd child. I am using a combo of readingbear.org, readingeggs.com and various beginner readers (Bob books, all about reading readers, others). I have not used an official curriculum with her yet because I feel she is too young for formal sit down instruction. When she is ready, I think I will use aas & aar.
ABCs I would say is a reference tool...lists spelling rules followed by a list of words. I bought it in the hopes of using it for making my own spelling curriculum but have not really found a use for it.
I own a lot of phonics instructional programs...not one is a dream come true;p
Boring but has be effective-Phonics Pathways (kids did not enjoy this one but it got my 1st born reading). OPGTR I feel is thorough but was boring for my kids (not quite as boring as phonics pathways).
Fun but expensive-The kids and I enjoy the aas & aar programs. Easy to implement (we do not use the tiles, cards with either program). I do not like the price tag nor the fact that I have to go through so many levels. If it came all in one book I would be in love. I have only used levels 1&2 of both programs.
I bought LOE Essentials...nice instruction but again boring for my kids.
Hope you come up with something that will work for your family.:)