I have no experience from Dogma, but it seems to me that they are an Adult Video producer and the onaholes are based on their actresses or film series. And often onaholes that are based on AV stars are not good. Buf if you find a potential onahole that looks nice, search for it on
http://onahodouga.com/ or http://www.amazon.co.jp/s/ref=sr_il_to_hpc?rh=n%3A160384011%2Cn%3A%21161669011%2Cn%3A171288011%2Cn%3A2132581051&ie=UTF8&qid=1378425133&lo=none and maybe there are reviews.