Best is too subjective to have a black and white answer.
I like the 280, 7mm-08 and 7 x57. I'm not a big 7mm Rem Mag guy but a lot of people buy it, use it and love it so I can't agrue that it's not the best.

The 7WSM, 7WBY and even the 7-30 Waters all have people that swear by them.....who's too say that one of these or one of the less popular 7's, like the 284 Win, isn't the best.