I wanted another headset that was mini-jack and as these were dual purpose, a seemingly rare option, they appeared to fit the bill nicely.
They were delivered within three days of ordering so no complaints there.
Sound quality is very good (at both ends, I'm told!) so no complaints there, either.
On the down side, compared to my existing, similarly priced, two-year old (but seemingly no longer available) USB Logitech set, design of this Plantronic headset is very basic and they are considerably less comfortable to wear due to a stiffer headband making them rather tight on the ears and (despite my pen name above!) I really don't have a big head! This is not helped by the ear pads being rather hard and flat and having no padded ear cushions. By contrast, and in addition, the sliding adjustment of the headband lacks stiffness and you may find yourself having to continually re-adjust them.
I did buy these with the intention of them becoming my primary set but whilst the added features of a volume control and dual connection are handy to have but not necessarily or continually vital for my purposes, the relative lack of comfort has let them down, especially when worn for an hour or more!
In fact, unlike my Logitechs, I certainly doubt that I could ever again get up and walk away from the computer having forgotten that I was still wearing a headset and, for that reason, despite this possibly favourable and subtle "safety feature", I'll be keeping the Plantronics as a secondary pair only!