How would a recorded lease protect my home purchase?

A poorly written master lease applies to 10 privately owned waterfront homes. The leaseholder says she would consider a new lease written by my lawyer, as long as it never gets recorded at the courthouse. Naturally, no bank would mortgage a home on leased land, so we are looking at a very big cash deal. My lawyer says, without recording the lease, I would be subject to vagaries of the leaseholders' lives, economic choices, and decisions by taxing authorities and creditors. I don't want to cloud the land title, but I would like the right to live in my own home for 20 or 30 years. What are the pros and cons of recording a lease? It's not too late, should I walk away from the proposed purchase?