Importance of certification? American? European?

I am in the market for a ring.

Should I look at anything not GIA? I saw a E vvs11.61 rock but it was certified by a co I never heard of. The sales Oman said it was a German co. The initials were DGL. Now I've heard of EGL but not DGL. Anyway, I don't know how that translates took GIA grading.

Should I just only bother with GIA?