I have used both their electric and acoustic strings.
The electrics were quite good (very good for the price), reminded me a bit about D'Addario. But I find Pyramid strings just as good, if not better, and I can get them at a similar price in Europe. For the USA and Canada Webstrings are probably the best choice in terms of value for money.
The acoustics left me cold; Can't put my finger on it, but they were without personality and real "tone". They were also quite stiff. Don't know, perhaps I got a bad batch, because I only tried 3-4 sets.
I sincerely believe it's best to buy cheap strings and change them more often, than more expensive ones. DR Strings have fabulous tone, but at the same price I can get 3 sets of Pyramids or 2 sets of SIT which give me most of the tone for a lot more time.