I hate to recommend people a phone, but if I wouldn't go with the iPhone4 today (which I wouldn't buy knowing iPhone5 is now around the corner) I would consider the HTC Desire HD, but I am not an Android fan at the moment.
I spend the extra $100 and went with the iPhone4, and I am not regretting it. I know others have a different experience or opinion. But you asked for mine
I don't know of quality smartphones for around $150.