It doesn't matter much. I think both are good. Anime (S1, haven't seen S2 since I've been reading the manga since S1 ended/scanlations appeared pretty much) has some fillers (i.e. more content) and a very rare example of a canon arc that didn't appear in the manga (although it gets referenced sometimes). As such I think watching S1 of the anime is worth it but I have no idea what S2 looks like. I imagine it's a more straightforward adaptation so you can start reading the manga after you finish S1.
For the biggest part I think it's a matter of preference. Would you rather watch an anime or read a manga?
It's worth noting that Ritz has a brilliant background assistant, though.