> where just one title was accessible

Well the first printed Perl6 book I saw was 15 years ago. (no joke, I had it in my hands =)

> the number of pages? the index?

Personally?

• I'd look at the index and read the free online chapter and potential reviews.
• Than I'll decide which style I prefer and where my priorities are.
• Than I'd chose one or two.
• If you are still lost take the cheapest or toss a coin.

BTW: IIRC is O'Reilly sending free trials to Perlmonger groups, if they promise to write a review. (dunno about apress)

My book store would allow me to order them all and investigating them there before I choose.

Or probably you'll find send back options at online stores too.

(

If that's not enough, sorry it really highly depends on taste...

• some prefer a good academic structure and cross referencing ,
• others want plenty of simple hand on examples to copy the code,
• others want an entertaining language with jokes and anecdotes
• ...

)

HTH! :)