g1smd - 4:16 pm on Oct 25, 2012 (gmt 0)
Yes. You must test with both www and non-www requests. Use the Live HTTP Headers extension for Firefox to look in detail at the reponses. You need to make sure there are no chains. Try also adding another junk parameter on the end of the request and make sure that request is also correctly redirected.
With only 18 redirects, doing this in htaccess is fine.
You may want to try out the "rewrite to a script" version so that you are familiar with it for when you need it on a really big site. I'm using it to redirect 80 000 duplicate content and old-style URLs to 1200 new extensionless URLs on one site.
The stuff about correct "404" responses was for when you use a PHP (or other) script not a pure htaccess solution.