seo addon redirect more

Couple quick questions:

  1. Site has been up over a year, today I changed the SEO ADDON url for each item so that it doesn’t use the category names in the URL as it has been.

    I added a rewrite to my htaccess so that the already indexed google links will redirect to the new URL.

    a) redirect permanent /category


    B) RewriteRule ^category/(.*)$$1 [R=301,L]

    Is either of these ways better than the other or does it make any difference? I tried both, they both work.

  2. How much benefit would I get from using one of the canonical URL addons? And will it have any conflict with any of the above?