User blog comment:B214/Volume 23 discussion blog/@comment-1359322-20170318060342/@comment-9595671-20170319034507

I agree, that explains why Rias needed to use all her Pawns for Issei despite how weak he was at the start of the series. Any Longinus equal to or below the BG and DD would have likely been the same.

The high tier gears on the other hand? Had Issei had any of them, I don't think Rias would have been able to reincarnate him unless she had mutation piece pawns from the start.