You can't beat xline brushes.
I bought a Gardiner's medium ultimate last week, used it for 1 house, took it off and sold it to a mate the next day. It felt like a toothbrush on the glass, there's just not enough bristles on them.
The one good brush Gardiner's make are the flocked sill which are great on fascia's and cons. Not so good for everyday use though.
Not everyone cares about lightness. I want Gardiner's to make a brush with as many quality bristles as they can pack onto a brush head.
Xline brushes tend to have a row of 3 outer bristles, whilst Gardiner's only have 2, or even 1 on the extremes. I'd take the slightly extra weight for better scrubbing power and longevity anyday.