The LC bearing made by Glacier are a copy of the Vandervell VP2 Cast Cu/Pb overlay plated bearings, they are Sintered Cu/Pb not cast and the overlay is Tin/Pb instead of Tin/Pb/Indium. This will make they slightly less durable in a high performance engine as the fatigue strength is down by 5% or so and the lack of Indium means if the clearances are tight there is more chance of a seizure in the first 100 miles. The differences were to get round patents held by Clevite on the Cast Cu/Pb process and Vandervell had a license to use the Cast process. LC stand for Lead Copper.
In short if you have them then use them, there is nothing too different to warrant not using them and buying NOS VP2 or the Andover modern copies.
As the for the last 20 years or so the main spares available are Al/Tn bearings with no overlay (not needed as the acids in the oil do not affect Al/Tin) and no one has raised an issue then a drop in 5% fatigue strength is nothing as Al/Tin bearing are a further 20/30% lower. Its like a dam, if you never reach the peak figure there will be no effect, so Cu/Pb only needed for racing applications in a Brit twin.