I am sure that it will become "LR" once seeded, but that does take some time. It's the same idea in using Utah rock. Use it as a base and seed it with LR.
But, it really depends on shipping as to whether it is worth it or not. The website has it around $1.42/lb shipped, so that's not too bad. It looks rather bleached though and being mined from a quary bothers me a bit. Also, is it lava stone or is it old coral like alot of LR is? I couldn't really find that answer on the website.
But hey, it looks like a decent deal to me. Definately something worth considering!