transitioning workflow from mov XDCAM

[RAILND]

Hello all,
in our production office we have been working with FCP7 for several years. The majority of our footage archive is in .mov XDCAM EX 1080i 35Mbps.
We have been transitioning to PCs running Adobe Premiere in the last years and we now are stuck in a situation where the old files can be read by Premiere Pro but we cannot generate .mov XDCAM files anymore.
As an alternative we started using MXF with the XDCAM codec, but the lack of ability to write metadata is hurting us. 

So, what format/codec would you suggest we migrate to?
Storage space is an issue for us, that's why we opted for a light format such as the XDCAM EX.

Any additional info you might require, please feel free to ask.
Any suggestions is appreciated, thanks!

[Rick Gerard]

I would pick a version of ProRez that has what you need. I always try and keep my footage at least 10-bit and never intra-frame compressed (MP4 - MPEG). Storage is so cheap now that it doesn't make sense to throw away the color values you may need in the final edit. As soon as you convert a file to 8-bit, you are limited to only 256 different values for Red, Green, and Blue.  ProRez 422 LT is capable of 10-bit and ProRez 444 supports 12-bit and 16-bit for the Alpha Channel. 

ProRez Data Sheet

Read up. This might be a very good solution for you.

[RAILND]

Thank you Rick, appreciate your input.
Regarding the quality issue, I surely agree with you, however we work mainly for the news and we deal with footage that comes to us already compressed. We convert it to allow a smoother edit.
I also agree with you that storage is cheap nowadays, unfortunately we depends for our storage facilities from our head office which is always very strict on costs, so we try to make the best out of our situation. Many thanks!