Urban's CPerl actually in many cases speeds up stock Perl5 code when there is no magic and falls back to comparable speeds to mainline when there's Perl magic involved.
Neither of these projects is part of mainline Perl. They are both forked and little has made it back to mainline largely because they have different goals but also due to personal conflicts these two have with large swathes of the community.
Both are very competent developers. That's not the problem with them trying to speak for the community they have rejected.