Hi! First post here, I don't normally post on forums but thought I'd drop my 2 cents in here for those swayed by others' opinions.
Overall I like it! It is very entertaining and I love the interaction between the characters, very funny. A good change after so much seriousness for a while Each character is just as alive as any other Conan anime/manga/move/OVA you name it. I won't say much about the plot for fear of giving anything away, you'll have to watch it.
A rule of thumb that really should be applied to anything: don't go in with expectations. It is expectations that either disappoint or satisfy people.
This is coming from a fan that has watched every single anime episode, OVA, magic files, shorts...what you have (minus reading the manga).
Enjoy!