Steam Detectives suffers from the simplicity of its stories. Although it's not quite on the Scooby Doo level of simplicity, it's not nearly far enough above it. The villains are of the masked variety, with nonsensical schemes and goals. The steampunk--high technology based on steam power--setting is interesting enough (if derivative, considering the recent wave of steampunk stories), but it's really wasted. It's not so much that the stories here are bad; rather, there just isn't enough to them.
The art can either save this book or harm it. I've never been a big fan of Kia Asamiya's artwork--the noses of his characters are just too big for their faces (in length and width), and it doesn't appeal to me. Steam Detectives doesn't suffer this nearly so much as other stories (Silent Moebius, for one), but the artwork is also simpler and more stylized. My recommendation: click on the cover art to get a larger view of it. That's what the art looks like, except the book is black & white. Some people love the look of Kia Asamiya's artwork, so take a look at it and decide.