Perl::Shell is limited compared to the other Perl REPLs, notably Devel::REPL. Some omitted features that stand out out are the lack of a plugin system and the lack of a feature for remembering lexicals between lines. It's nice to say:
>>> my $foo = 42;
>>> $foo / 6;
Devel::REPL does this out of the box, but it's not currently possible with Perl::Shell.
Anyway, I'm aware that the author wrote this because Devel::REPL's re.pl script causes problems on w32... but I think a patch to D::R would be a more acceptable response to that problem. Devel::REPL already has quite a few authors (notably mst and Sartak), so it's not like the project is avoiding external contribution. I think I even have some code in there :)
Anyway, by patching Devel::REPL, everyone could immediately benefit -- w32 users would instantly have all of Devel::REPL's neat plugins. Instead they are stuck with this half-assed attempt at a REPL for the foreseeable future. Better than nothing, but pretty anti-social.