Translating the Son of God to Muslims

Faithful translation always requires contextualization.  If the intent of scripture is for God to reveal His purposes in Jesus Christ to all people, then our translations should be faithful to that purpose and strive to make scripture accessible to all people - while still remaining faithful to the original text.  This balance is often tricky especially when it comes to recognizing what might be more idiomatic language which is often very culture bound.  Is it ok to translate αδελφοι as "brothers and sisters?"  Contemporary translators seem to think so, and I tend to agree.  Is it ok to translate "kick against the goads" as "bang your head against the wall?"  Well, perhaps...if you're paraphrasing.  Is it ok to translate "Son of God" as "the Beloved Son who comes (or originates) from God?"  I must say that this makes me very uncomfortable, but this is the current debate revolving around the translation of the NT into Arabic.  Is the "Son of God" an idiomatic phrase which should be flexible in contemporary, contextualized translations or is there something about that specific title which communicates an important and essential truth about the nature of Jesus Christ? Ed Stetzer on his blog, shares a very thoughtful and critical response to this recent trend (most recently expressed and defended in an article in Christianity Today) of contextualizing the title "son of God."  The newer and less offensive translations have proven incredibly effective in reaching Muslims, but nevertheless the question remains: is there something about the title "Son of God" which is more than mere idiom and must be retained in our translations regardless of how it may cause others to stumble?  After all, a crucified prophet is a stumbling block to Muslims as well.  Mere pragmatics and the itching ears of culture cannot guide our translations.  This is a question which reaches far deeper than the contemporary gender-inclusive debate circling around many newer translations.  This contextualization question goes to the very heart of biblical christology.  I strongly recommend reading both articles.