There's nothing remarkable about the construction of this Powerplay stem, and that's a good thing, in my opinion: making stems out of simple aluminium tubes is still the best way to get a good balance of stiffness and weight.
This stem will hold your oversize bar nice and tightly in its four-bolt clamp, and it's plenty stiff for even a big rider like me. At 145g it's not a featherweight, but there are plenty more expensive stems that aren't as stiff and weigh more, including many carbon ones.
In fact, it'd certainly be one to recommend if Powerplay didn't rather shoot itself in the foot by making a non-lite version too, that's about 10g heavier and £10 cheaper, and available in a wider range of lengths.
Given the choice, I'd save my money every time. If you think the slightly sexier clamp and tiny weight loss is good value for your tenner, that's your call.