Has anyone had on of these CD players? How good are they?

Lasers burn out, buy new. 

I had the 507 long ago, wouldn't buy one now...

I still have an old Sony XA20ES that still works like new. It is in a secondary system at present, so doesn’t get used every day. It has a drawer, but the whole laser drive and table drive are in a slide out assembly. It takes a puck on top of the disk. I think the laser drive slides on a rail. Sony used to use a linear motor on those units. Not sure what is in this one though. I did lube the laser rails a few years ago. I think the above advice is spot on. Mechanical stuff does wear out.

X707es would be my choice as a transport, if i had to choose between the three you mention, cannot go wrong and rarely does get better than this.

One issue, check that laser is ok, normally it would last very long time, the one i had in the past is still spinning, also note that these units are not supported with spares any more.

I owned the X707ES for many years.  Good player in its time but not so special in stock form by today's standards.  If you are looking for a good transport you would be better off buying a Rega Saturn.  Very musical and good quality.

Happy Listening.