Just to add my thruppence-worth.
I've a PPL with about 110 hours, and am also a fan of GA simming. I think there's definitely a place for the sim as a tool (primarily in instrument work) toward training.
I can't say for definite whether flying Navaids on FS saved me money during my training, but it definitely helped. Having some knowledge of how things "work" saves precious time in the air and allows you to focus on how these things are applied in the real world. Certainly several hours spent bumbling about on FS is more cost effective than flying backwards and forwards over a VOR beacon in a Cessna trying to understand which way the needle should be pointing.
While simming is clearly no substitute for the real thing, I think it can make your time in the air more focused and enjoyable.