^ Yes, it's peak is mis-leading. Last time I checked, it was the 2nd best-selling song of the year that missed the top 20. I doubt it's sold as much as 300,000 though, but it's sold almost as much as the top 10 hit, Hold It Against Me.
It was massive in the US though, with it peaking at #3, and spending over 2 months in the top 10. I think it would've been that big in the UK if it had got the radio airplay that Hold It Againt Me got.
There's no point in Britney releasing anymore singles though, at least from the UK's perspective. Radio aren't supporting her anymore. The next chance she has of having a hit here is with the lead single from her next album tbh. Or if she features on someone else's album.