That module's neat, but CPAN is still out of reach. For one, a lot of important modules in CPAN contain XS components, which don't carry over. Additionally, a lot of the modules that don't use XS are likely to be using unusual features of Perl5 which aren't fully emulated by that shim.
Yes. v5, a Perl 5 compiler written in Perl 6, is promising tech with potentially huge long term (10 years) strategic consequences for Perl 5 and Perl. But it's very early days and it correctly handles only the simplest of modules. I'd hazard a guess that currently less than 1% of CPAN modules pass their tests when loaded by v5.
But Inline::Perl5 is a completely different animal. It handles modules using XS or whatever fine. See my nearby comments for further details.
As its now been pointed out more than once, 'not at all' is not true. I did not claim it could use everything available on CPAN, but was pointing out that you were making a false statement based on, well, i'm not sure what you based your statement on but it was made in such a matter-of-factly way that it needed to be corrected.
While not quite the same as what was asked, it's clear that 'not at all' is not an informed answer