while what bust says hold some true, what violent beams imply could be applied to prison and perhaps u guys could do exactly the same exp or a bit less but killing more mobs (5 players, more kills per hour, less exp per mob) which could compensate.
that said, it could be worth to say that if you for example have a team of friends, or trustful ppl who you want to climb with you may consider this as a suitable way to PG, specially if you guys are planning for example do daily bosses and 5-man content, anything bigger than 5 player probably isn't any worth on exp at all.