ping to 70. Have you heard of this? What's your opinion?
However, from what I've seen in this article, it is a little unclear as to what the non-fuel waste products are or the actual efficiency ratios. It says it's up to 90% efficient based on the feed stock, but that's not saying much. I strongly syspect that if it's only 90% efficient with an ideal source material, then its efficiency with real world feed stocks will be considerably lower.
All that being said, the fact that they are actually trying to sell working plants, and not just hoping for "investors" is a really good sign. That says to me they really think they've got something, and aren't just another "free energy" scam.