Yes, they are a great way to manage a ton of discs.  I have four of them in my main room, and two more in the bedroom.  I use an MX-3000 remote with DMX-3000 software and DVD Profiler to put the thumbnails onto the remote.  The end result is a system so easy to use that my four year old uses it to choose her own movies without help.

My Epinions review of the changer is here:

http://www.epinions.com/review/Sony_DVP_CX995V_Multi_disc_DVD_Player/content_422604082820

The DMX-3000 software is here:

http://www.triplebsoftware.com/DMX-3000/index.htm

There is more information on using the remote with it here:

http://www.remotecentral.com/cgi-bin/mboard/rc-master/thread.cgi?5802

Basically, the 995 cannot be computer controlled because it doesn't have a serial interface.  The ES version of the player, the 777, does have a serial port on the back, but is twice the cost and doesn't have an HDMI port.

For 300 disks, I would just get a single 995 and use DVD profiler to keep track of the locations.  If you expand beyond a single player, you can consider going the MX-3000 remote path to make things more usable.

I wouldn't bother with the built-in disk tracking software.  It is slow, cumbersome, and isn't worth bothering with.

Sean

Quoting splogue:

Quote:
Yes, they are a great way to manage a ton of discs.  I have four of them in my main room, and two more in the bedroom.  I use an MX-3000 remote with DMX-3000 software and DVD Profiler to put the thumbnails onto the remote.  The end result is a system so easy to use that my four year old uses it to choose her own movies without help.

Oh my god... 
Errm... do you have some pictures of your setup and the remote?
I would really love to see that system.

Quoting splogue:

Quote:
Basically, the 995 cannot be computer controlled because it doesn't have a serial interface.  The ES version of the player, the 777, does have a serial port on the back, but is twice the cost and doesn't have an HDMI port.

Well I wouldn't say can't. Maybe not ideal, but LoadDVD controls them via IR signals. With LoadDVD, you can control up to three CX995Vs (there are three code sets), one or more CX777ES (serial), up to 5 VGPXL1B1/2/3, one CX950D and CX860 - that's nearly 3000 DVDs. Checkout the LoadDVD thread for lots of user comments and feedback. Each of those units I either own myself or have direct user feedback of successful operation with DVD Profiler. Once set up, the user doesn't know or care where the DVD is coming from.

By the way, you can also play files from the harddrive and select DVDs for manual handling from Dacal/Ziotek style USB-connected carousels (127 x 150) - another 19,000 DVDs!