Anyone heard of Jimmy's?

[ProfJenn]

Hi folks!
We'll be in CA for a visit to DL in June and my DS (6yrs) saw an ad for a "jimmy's hot wheel" store. I've seen their webpage ad it looks somewhat like a flea market (with independent vendors, etc), but it's hard to tell.
Has anyone heard of this place? Anyone been there? I don't want to give up a DL day if it's not much - but if it's impressive, then I have a Hot Wheels fan that might like it more than the parks...