Are there issues with doing that?

It can easily fail:

#!perl -I.
#t.pl
use strict;
use warnings;
use XTest;
print "ok\n";
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#XTest.pm
package XTest;
use strict;
use warnings;
1;
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F:\tmp\test>dir *.p*

 Directory Listing of F:\tmp\test

01.06.2006  20:02                   52 t.pl
01.06.2006  20:02                   46 XTest.pm
               2 File(s             98 Bytes
               0 Directories,       2.727.182.336 Bytes free

F:\tmp\test>perl t.pl
ok

F:\tmp\test>cd ..

F:\tmp>perl test\t.pl
Can't locate XTest.pm in @INC (@INC contains: F:/Perl/lib F:/Perl/site
+/lib .)
at test\t.pl line 4.
BEGIN failed--compilation aborted at test\t.pl line 4.

F:\tmp>
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