It all depends who ports it. When the Serval’s came out guys like Cam and Jeff were both posting dyno results of porting that netted gains all around with just tunnel clean up, re shaping and better angles. No duration changes. All torque and HP. No loss down low. Similar results on smaller in frames and in frame drag pipes.
You want bigger carbs and pipes that are made specifically to do what you’re saying you don’t want. Smart Carbs really aren’t cracked up to what the advertising says, and Shearers are a top end in frame drag pipe. Are you chasing a magical number or are you setting it up for digging out of tree shots?
There is so much R&D out there that folks know what does what and if it’s ported right, you won’t lose anything down low, in fact you’ll gain everywhere.
Snipers on Servals have proven to make more bottom and top than the Shearers, although if you want it more for tighter technical riding, the CPI’s you mentioned would be great, but you might need to track down a big bore set or make new stingers.