Should I use Replay Gain on Flac rip?

[longhorn]

I have started ripping my collection and am using replay gain (DSP). I have recently read some material which makes me wonder if I should be doing so. Apparently, some people think that the files should be ripped as they were originally mastered. I know replay gain only changes the tag but I will ask the following anyway.

If I wanted to reverse this later (after ripping 100s of CDs) is there a way to do so for a very large batch of files?

Is it problematic or a relatively consistent and easy process?

Do you think it would be better not to rip the originals with the replay gain tags and add them later or simply continue adding this DSP while ripping.