[MENTION=40398]Tequila Sunrise[/MENTION], hi. I directed them both, and did the bulk of writing.
WotBS was meant to fill a hole in that 3rd edition hadn't released any grand war adventure paths, not like Dragonlance. Ten years later I can see its flaws, but I still am proud of it, and think there's enough material that players would get invested in the setting and characters, so that later adventures would have a satisfying pay off. However, I wasn't involved in the 4e conversion, and from other people's comments it suffered from being released fairly early into 4e, when the kinks of the system weren't worked out. Early on monsters have too much HP and don't do enough damage, which was a common problem in early 4e.
Also, a strict following of the XP guidelines meant that the conversion had to add more encounters to get the PCs to 30th level. This led to some added plot threads that people say clutter the core narrative. I haven't read the conversion, and I don't want to besmirch the work of other writers. However, I know 4e combats can take a while to run even in the best conditions, so the extra material might not be the best idea if you want to finish before WotC publishes 6e.
Now, ZEITGEIST I'm still in love with because I just finished it in the past year, so I don't have the distance to critique it. I think we did excellent work in giving NPCs compelling conflicts, interesting personalities, and the occasional character arc the PCs can play a role in. The setting is, yeah, loosely inspired on 19th century Europe, but I shot for it to be a fantasy world that is going through an industrial revolution, whereas I feel like most steampunk stories start with 19th century tech and then just toss in magic or gizmos with no history or grounding.
My goal was to create an exciting story that threaded in elements inspired by real cultural and political challenges so, if you're in the mood for it, you can use it as a way to examine the real world. Or you can just run it as Sherlock Holmes-meets-The X-Files. Also, to be totally honest, I was irked that a lot of TV shows that set up long-term mysteries (namely LOST and The X-Files) clearly didn't have a plan for the revelation, so I made sure before we started to work out how the mystery would unravel. I wanted to make sure we weren't just adding secrets to pad the running time. And thanks to years of advice from great GMs here on EN World, my own experience running, and lessons learned through designing WotBS, I feel confident that the ZEITGEIST adventures provide a dramatic, dynamic story while avoiding railroading. Even in the adventure that literally involves the PCs on a train.
So, well, that's my horn. Toot toot. If you want to get a fuller sense of the campaign, there are a lot of GMs who post on the E.N. Publishing forum about their campaigns.
To [MENTION=22362]MoutonRustique[/MENTION]'s comment, I still did all the conversions to 4e on the adventures that were written for Pathfinder. I love that 4e lets you pace fights well and create all sorts of brief threats that need to be dealt with, as opposed to 3e/PF's style of "did you save? you're totally fine with no narrative effect at all. did you fail? you may as well take a nap."
(I wish 4e had not had the odd math where everything scaled so obviously for the good guys and bad guys, and I wish there hadn't been so many niche powers, feats, and magic items that clogged up the character builder. But you could run the game with just the physical books and you wouldn't be overwhelmed with options.)
The best suggestion I got for ZEITGEIST encounter design came from [MENTION=1]Morrus[/MENTION], who insisted every power of every enemy have a short sensory description. That led to me, later in the campaign, using that description section to work in dialogue that enemies might say during the fight, to give the fights more personality. I found that often when I converted a monster from PF to 4e, I'd add some more tricks or narrative beats to its attacks, and then go back and add those to the PF version too so the Pathfinder players wouldn't miss out.
Like in adventure 5, one encounter has some gremlins, which in PF just make you roll twice and take the worse result. In the 4e version, I instead tweaked the mechanic so they specifically messed with guns - if you tried to shoot at them, the gun would click but not fire, but if you stayed still and kept aiming until the start of your next turn, it would fire then. If you moved before then, the gun would go off as soon as it wasn't aligned with the gremlin. I put that same schtick into the PF version, even though it sort of goes against normal Pathfinder design conceits, because I felt like it offered some fun decision points for players.
(Also, the main fey foe of that encounter causes any ranged attack that comes within 10 feet of him to divert to another target. So after the first couple times you shoot at him and strike an ally, you might decide to try shooting at an ally, which - yes - will cause the attack to divert and hit the boss.)
Tequila Sunrise, what are you looking for in an adventure path? What do your players like?