[support] organization question

[Vasiliy G Tolstov]

Hello. I have 2 sites - first for stories and blog and second for shop,
runs on ubercart. Two sites runs on different domain names

Which solutions is best for performance, seo, stability:
1) install all needed modules (ubercart, google analytics and other) in
only one site (shop available for example on /shop/
2) install all modules in separate sites (like now)...?

P.S. Sorry for my poor english.

-- 
Vasiliy G Tolstov <v.tolstov at selfip.ru>
Selfip.Ru