E28 535 questions and WTB

[Eric Rayl <ericrayl@xxxxxxx>]

Please excuse the WOB if this got to the list 2 days ago and I missed it.

A while ago I decided I needed a inexpensive 3rd car to rescue me from
family mini-van and front wheel drive wagon hell.  Been lurking here for a
bit to get a feel for what I'm getting into, and the 535 seems to fit my
criteria nicely.  This forum and other BMW info. available on the net is
fabulous.

Anyway, the questions:

1.  What are the differences between the i and is?  I'm trying to dicide if
it's worth the roughly $2k extra for an is and haven't found this whole
story anywhere.

2.  How common or rare is a limited slip diff. in the i and is?  How does
one tell - I.D. plate somwhere on body, tag on diff, appearance of diff, or
what?

3.  Anyone out there know of a good example for sale, must be manual trans,
no rust, good paint, engine and trans., under ~150k Everything else I can
deal with.  I ask because 535's seem to be higher priced here in Seattle
than elsewhere in the country so I'd travel some distance to get the right
one.

Many thanks, Eric Rayl
ericrayl@domain.elided

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