I've bought a handful of gameloft games. At this point I've deleted them all from my device.
I wouldn't make the argument that they're not worth what they cost. However I would say that I like gta 3 more than the gangstar series. Real racing more than asphalt ( not that the asphalt series is bad, or worse even than the nfs mobile games ). MC3 was good. Not my favourite FPS on iOS.
Obviously some people really like gameloft. Others really hate gameloft.
I'm in the middle. I appreciate gameloft for their success. Their failures have been fairly serious ( the freemium fiasco and possibly the upcoming paymium period ). I'm willing to give them the benefit of watching to see what the future holds and hoping for some great quality titles. I won't be holding my breath for them to redefine gaming on ios platforms though.