Look at the dates. That's only one complaint per year on build quality, not bad. I've seen way worse on Amazon. There's also threads on head-fi.org and they don't seem to imply a build quality problem. But I don't think I'd like what appears to be a non-removable cable, so I wouldn't consider the T70P.
But back on topic, I bought a used pair of SE H6. They are plenty loud and have tight bass. I'm pretty sure they are already burned-in but I'm surprised at the amount of volume. People have said these are low volume. I'm not getting that. I'm not using an amp and I cannot listen at full volume, too loud. This is on a laptop and iPad.
I do have to say that on an iPhone 6, I do have to crank the volume to about 75% or 80% to get into partying mode. But still not to where I need an amp.