I can offer you no advice except from what I have read and heard. When I mentioned buying one to my BIL who is an aerospace engineer, he had that look on his face of naive disagreement, but said nothing. I knew from the look he wanted to say something but was holding back. I asked him did he have an opinion on them since he has several engineering degrees, mechanical civil and aerospace, and he said, "wait until the next generation, they will get better."