VNX5300 RAID-6 Transition Plan - is it worth it ?

Hello,

on VNX5300 we have two DAE (25+25) used for File.

Currently they are organized as follow:

4x reserved, 1x hotspare, 9x RAID-5 (4+1)
The total available capacity is therefore 9 raid x 4 disks x 600gb = 20TB

I was thinking if it is worth to have this layout instead:

4x reserved, 2x hotspare, 4x RAID-6 (9+2)
Total availability remain the same 4 raid x 9 disks x 600gb = 20TB

The new layout would benefit of 2x hotspare and two redundant inside each raid group.
Because each DAE has 25 slots then the one raid-6 group has to be spread between the two DAEs while with the current each DAE has its own complete RAID set.

Thx!

A.