Does Anyone Have a Recommend Kernel for ResurrectionRemix 5.7.1

Hi to all... I have a M8 ( MID Changed from 0P6B65000 to 0P6B10000 ) device and i installed RR 5.7.1 and waiting for kernel recommends...

Do you recommend the Marshmallow update?

I just bought one MI 4. It came with KitKat. The performance is quite nice and everything is snappy.
Do you recommend that I update to Marshmallow? Has there been any performance issues, bugs etc.? :confused:

Can someone recommend a good battery charging pack case

Could someone please recommend a good one please you S7 T-Mobile version and when you guys are using the price we respected and liked a link to the site if possible I really appreciate it thanks