I have an older HP server ML350 G6 still in production. I have a drive out on the 6-drive RAID5 (the lights are green but faint). In looking for a spare I ran across 3 potential replacement drives in the lab. BUT they are not identical and Im not sure if they are recommended to attempt to replace. The drives in use are 72gb 15k 6G. The one replacement I have is brand new but it is 72gb 15k G3. Would this matter in this config? Could I use it without incident? The other 2 drives are old used server drives on hand. They are both 72gb 15k but there is no G6 or G3 labeling. Same question on those - would they be acceptable replacement for the failed drive?