I do have the 35mm adapter and mask, but haven't used it yet. In fact I have the original case and all accessories - even the Yashica branded cloth satchel of silica gel that keeps the moisture out of the case!
And I do agree with you Rick, it's just easy to use. Everything is just there, no juggling from hand to hand to change settings - it just works. Not too big, not too small, but just right. And the images it makes are just beautiful.
Mine shoots fine, but I do want to send it in for a full CLA and de-dusting. The guy whom I bought it from must have kept it inside the vacuum cleaner or something!