FTWGuides leveling guide currently goes to level 30 for both factions, which I should note sell separately unlike Killerguides leveling guide. FTWGuides Aion leveling guide is pretty detailed and includes maps and some tips and tricks.
The interesting fact is that this leveling guide comes in online form, unlike other guides which are downloadable PDFs. It's probably a matter of personal preference which one you like more, but one positive side is FTWGuides has quests linked to AionArmory for quick reference.
Overall, I think FTWGuides Aion leveling guide is better than KFGuides and definitely better than Fantoms guide, but doesn't have what it takes to compete with Killerguides or Kozen's Leveling Guide which I recommend.