I think you won't get a better result. Especially if you use 480p.
The difference between 576i and 480p will hardly be noticable.
Today I attached my daughters Wii to the avant camcorder connnection. And I must say, it gives a fine picture.
Not superb, but the Wii isn't the best known for its video quality. For that you need the ps3.
And the BV6 has a 22" panel compared to the 32" avant, so the difference is more difficult to notice.