One of Vic's (90 syncro westy) Yokohama Y370s has a bubble, and Discount
tire is having a hard time finding a replacement (the tires are about 2 1/2
yrs-20,000 miles old, and have been rotated).  This makes me think that I'd
have more tire options if I had 15" wheels.  Thus, several ?s:

Steel or alloy?- Discount Tire can get me a steel 15x6 wheel, 112 mm bolt
pattern, 35mm offset, basic black, for $35 each, which seems like a pretty
good deal.  What's the advantage to an alloy wheel?

What size tire- I've seen notes on everything from 215-235, and others in
between,  I'm looking for better crosswind stability, wider tire selection
(in choices, not width of tire), and bolt on fit (on the ground and in the
spare well).

I don't seem to be able to find the vanagon.com pages on this stuff, so
thanks for your help!!!
John
SLC
90 syncro westy, Tiico powered