iScript BioRad cDNA synthesis yield - (Apr/14/2011 )

Hy forum fella,
This is krusty... new for you forum members, new for me. Useful tool! (I hope)
Is there anyone with an indication of the expected cDNA yield after a cycle of iScript cDNA synth. kit (BioRad)? I know it depends on RNA quality and quantity, but I only wanted to know if it is correct to expect a 100% transcription efficiency in the case of a "perfect" RNA sample, or if this percentage is lower. And, in the case of lower quality and low-concentrated RNA (c.a. 15 ng RNA), is it likely to expect very low efficiency? (e.g. 10% or lower)
Any help is appreciated, any reference as well.
Thanks in advance
Bests
K

Still no one with an idea? Please!!!