For a shifting clutch, like the manual band IF pulling down for engine braking, the HE friction material is more durable. For the bands I have no preferrence though if you have to buy them they are very close in price and the HE lining is a little better. If the forward or reverse bands are burnt it was for a reason, not because the band wasnt doing its job. I have also find that HE linings generally like a little higher pressure to get the job done for shifting clutches but they will tolerate slippage or slow engagements much better than normal tan or paper linings will. HE frictions are great and I have been using them in 700R4/4L60E performance builds for a long time with great results.