Single buffer with N frames or double buffer with N/2 frames? Which one is the best?
Personally I use Single and keep the latency low. I think if you’re needing any more headroom then just increase the buffer. I did try double buffer for a while but any benefits were nulled by the double latency. I don’t have a super-PC/laptop but I don’t have any issues. Something to keep in mind also is that I believe in the 44xx builds Brad is working on Double buffer will be removed; https://community.cantabilesoftware.com/t/a-tiny-tale-of-woe-aka-what-happened-build-4400/11908
The mixer/interface i use most often (Zoom L6) has a fixed sample rate and buffer size. The only way for me to avoid clicks, pops, and other nastiness is to enable double buffer in Cantabile. I’m hoping @brad will reconsider the removal of the double buffer option.
Actually, what I was asking if that would any technical or practical difference between single and double buffer keeping the same latency, that is, single buffer with, would say, 256 frames vs. double buffer with 128 frames packets.
Apologies - I misunderstood your question. Technically I’m not sure I could answer but (perhaps as my audio laptop is not so highly spec’d - it was in 2017 
) but I found I’d suffer with CPU spikes when using double buffer even though they look the same but I’m guessing the double buffer is adding some overhead. So I’ll leave it to more knowledgeable folks here but personally I noticed a performance impact when doing the same (e.g. double buffer with half samples) - but that could just be my rig!
edit I should add that while my laptop is poorly spec’d these days I do use an RME Fireface 802 which provides excellent drivers to help with my latency and maybe compensates