Not US reader and I haven't read it in english, but:
In Poland only first story was published in 2008. At the back there was solicitation that second volume will be published in August. It's 13th year of waiting...
I decided to read it in Italian. Right now I'm after first Venerus/Marini story. My opinions:
WoM 2: Dark Age - First 3 chapters are the best. Mickey influenced by evil was the most entertaining thing in whole series in my opinion. Search for Great Armor (idk how it's translated) is slightly worse, but still good. Last part feel a little rushed.
Wom 3+4+5 (End of an era) - I expected that it won't be as good as previous ones. How wrong was I... First story is just good, some typical WoM story... But 2nd and 3rd, wow! It feels like it could have twice as many pages, but doesn't feel rushed at the same time. Exploration of background story of WoM world is also amazing.
WoM 6 (The New World) - I liked it. Phantom Blot is always good. First chapter introduces doomspiders. They feel like a pokemons a lot, but I like the idea. Second chapter with Trudy is my favourite from this cycle. Third one feels like a filler, only Phantom Blot past story was good there. Final part (or two parts) is return of quality ideas and I highly recommend it.
WoM 7 (Lemuria) - so this is probably the best part of WoM after Dark Age. Authors probably used all of their ideas there (this is the last Amborsio's story in WoM) and it feels like it, but also is a problem. Last 10 pages feel like a summary of 50 pages story. But the rest is great and I enjoyed it.
WoM 8 (Legacy) - so, say hello to Matteo Venerus. I stil don't know if I liked this story. It's more of 4 short stories with one theme. First one was mediocre, but Magica's one was really good. One about dragons was fun, but felt a little rushed. Final part has a good plot, but Phantom Blot is a little out of character, he wouldn't do things like these without good research and swot analysis lmao
WoM 9 (World's Mountains) - Hello, Roberto Marini. I really don't like style of his art. This is the worst looking mickey since Egmont stopped producing 3 rows stories with this character. Pastrovicchio's art was a little dark, with aura of secrets. Marini art looks childish and doesn't suit Wizards of Mickey series. This story is really nice, but nothing special.
At the moment: Ambrosio>Venerus Pastrovicchio>>>>Marini I hope next stories (Aurora, Magicraft, Oberon, Arena and Destiny) will be better, I have hopes - I think Venerus' plots can be better with a little of work and I think I will stand Marini's art if the plot is good enough.
Thanks! Maybe it would be best to have a dedicated WOM discussion because I could really reply a lot to this.
Although Lorenzo Pastrovicchio probably stands out as the most impressive artist of the series (no surprise he's back with the "Forbidden Kingdom" cycle), I do really like Marini. He's a pupil of Marco Rota, and you can see it especially in his Donald. Plus, the way he sometimes completely tears the traditional layout apart (combined with extremely detailed background art), is far out of the ordinary.