I have had 2 Sony phones in the household. My son owned the Sony Xperia Play with the PlayStation style slide out game pad, and the Xperia TL I think, the last Sony AT&T carried. I found them to be solidly built, well performing phones with the best call quality I have had since walking away from the BlackBerry Curve. I would borrow my Sons Play to make phone calls. It was truly that good.
Their customer service was excellent. The back plate got cracked on the TL, and they sent us one free of charge no questions asked. They were responsive and fun.
But Sony is losing money in all their areas. From Sony movie franchises (see what they did to Spider-Man) , to their communication branch for enterprise, to cell phones, to electronics and audio gear. Even the PlayStation- easily their most dependable money maker- is suffering due to Mobile's dominance for gaming these days,
As many posters have pointed out: Windows just ain't a sure thing for anyone except Microsoft's Lumia line. If it changes with Windows 10 and Sony thinks it can turn a profit they will be knocking Redmonds door down.
Put me in the column as someone who would happily give a Sony Windows for phone a shot.