Phone with sim or without sim?

[DK_TheOnlyOne_F54]

Hi there. I just want to know how much difference a phone without sim card makes competitively to a phone with sim card? How much battery is saved how more long it can survive? Is it worth to keep a phone without sim card?

NOTE:- Of course I have sim on another phone. So please don't tell me WHAT'S THE USE OF HAVING PHONE THEN? 

[AJAB_MORIA]

Yes, you are absolutely right but SIM card is required for outdoor use.

[DK_TheOnlyOne_F54]

That's why I carry both the phones.