If I kept the O2 sensors and the stock filter, I'd still need it mapped straight away?
Yup, because a full exhaust will run lean. You can damage pistons.
I had an Akrapovič open slip-on (CAT delete) on my 2014. An Akrapovič street legal slip-on alone requires no tune or ECU flash.
This can be found on their website, same type of warnings for full exhaust.
Akrapovič Slip-On with optional link pipe for Honda CB1000R must be used in combination with ECU fuel mapping enrichment, otherwise you risk severe engine damage!
For Dynojet Power Commander users:
PC III USB mappings available for HONDA CB1000R
www.powercommander.com:
M135-504 (with DB killer)
M135-505 (without DB killer)