I sent mine in but it wasn't a typical send in so my experience won't be the same as anyone sending into the repair facility. I have to say though that the reason for my experience being different will keep me with Asus for quite some time. Asus is about as proactive as companies get. It seems they have more than one person lurking in the XDA forum looking for new issues to investigate and it seems I had an issue they ID'd as something new they had to investigate. So they asked me to ship my unit to their US HQ, not the repair facility. (Which from what I've read is in Texas, maybe they have more than that though. Texas would have been closer to me than their HQ though.)
And I'll note, they contacted me first and got my info then had someone call me to arrange the RMA. I suspect if I had an already recognized issue, they wouldn't have done that and I would have had to contact them to do the RMA and sent it to the repair facility. For the repair facility, I had read a turn around time of two to three weeks total with shipping. I had to send in EVERYTHING but I've heard for general repair, they just ask for whatever part is defective.