1&1 hosting

[Cambridge PC Support]

I've got a 1&1 Home web hosting package which I've had for about 7 years

with it I've also got about 10 different domain names which 1&1 automatically redirect to my main website

does this mean that Google sees my alternate domain names as good from an SEO point of view? or as duplicate content

within my main website I've got an htaccess file set up which redirects some of my old webpages to the current ones from a rebuild I did a few years back

is it worth configuring the htaccess file to redirect my domains as well?