Only reason I made a tray for mine was because I wanted to make sure it was more secure and that it would also help with airflow over rad. Plus I can always replce to stock without any permanent mods.

Stz14s
 

Went with this battery per research, cost, and your suggestions. $40 shipped I mean c'mon. I only drive my RX-8 spring summer and early fall so, we'll see how it holds up with a little daily driving....