1. Hybrid LHB are a cheaper alternative, with ICF style suspension and bogies with the LHB style stainless steel body. Non AC LHB coaches have an MPS of 120kmph so, even if the trains are converted to pure LHB, for all the normal express trains which have sleeper coaches as well, there is no speed advantage as ICF can also go till 110kmph ( or 120kmph as seen in some posts, I am not sure about this though). So Hybrid LHB is a good alternative with the lower cost and well tested ICF bogies and the safety features for the LHB main body. But there seem to be some problems in the design and the results are not as good as expected from what I've read on the forums.