IMO
Rise of the Runelords is very good. Of other APs I've run/am running, Curse of the Crimson Throne and Shattered Star both suffer from the 6 book format. It leads to excessive padding by authors writing to the page count, and weak middle books - CoCT books 3 4 & (somewhat) 5, Shattered Star book 4, are pretty bad and mostly seem more geared to meeting the page count and leveling up the PCs than doing anything interesting. CoCT book 4 is so pointless I just skipped the whole thing, while SS 4 is a boring grind with a static villain.
But there is good stuff too - SS 1 and especially 2 were lots of fun, SS 5 & 6 feel suitably epic, and with 5 it helped a lot that big chunks can be skipped. Running SS6 currently, I find the main thing is turning lots of the given combat encounters into potential roleplay encounters. Luckily I have a really engaged player with a PC whose background as the de-stasised 11,000 year old Herald of Xin makes this easy.
Compared to WoTC stuff, the APs probably do contain more interesting stuff, a 6 book AP certainly will have more interesting stuff in among the padding than a single WoTC hardback. Neither are easy to use IME, though Rise of the Runelords hardback comes closest.
Edit: Mostly I find with the APs that mashing them up and using them as sources of ideas & NPCs works best. Paizo APs have tons of incredibly detailed NPCs with multi-paragraph backstories who sit in a room and "attack immediately... fights to the death". I like to get them out of those rooms doing stuff! The biggest issue with Paizo APs is that they are written primarily for non-playing readers. Adapting them to something good usually takes a fair bit of work, but is doable. The WoTC hardbacks seem written much more with the GM in mind, although they also tend to suffer from poor presentation and excess complexity in places.