Anything you replace the stock anchor with is basically an upgrade on weight alone.
Akras seem to be favoured as they are always good and designed for the SD. You can't go wrong with Leo's neither and they are cheap. I have Mivv's and they perform very good and they have been dyno'd at 115 BHP. Some members have the yoshi's and they look good, someone will get them dyno'd and we'll soon know how they go. I guess following yoshi's reputation they should be fine performers.
Plenty of other ones around that will rock i'm sure.