Lots of variables and personal tastes in how the knives fit/feel in your hand that only you can answer. That being said ... the small Inkosi does seem to have many people that report it to not fit their hand as well as the small Sebenzas, so that's something to consider. I only own a large Inkosi and really enjoy it, but I love my small Sebenza 21 Insingo.
For me personally ...
If you just want to compare the build quality and which knife has tighter tolerences and would be the most reliable and hold up to vigorous use over a lifetime the clear and simple answer is ... the CRK Inkosi.
CRK heat treats their magnacut pretty good and performs well. The CRK's steel will be much less prone to damage in heavy use over the S90V. The only advantage of the S90V might have is holding an edge a bit longer, but also takes more effort/time to sharpen.
The Inkosi is definitely a tougher build and will hold up to much rougher use and just in general, years of use. Benchmade's axis lock is prone to lint and debris getting into the lock mechanism and omega springs do break sometimes, CRKs are a simple and rarely need more than a cleaning and lube to keep them running extremely smooth.
If it's needed, CRK's warrenty is heads and shoulders better than Benchmade's in my personal experience. Also CRK's spa service is an added value to CRK ownership if that matters to you (as you can see below it's not a big factor for me, but to each their own).
The Bugout in S90V is lighter, but for me that's a disadvantage. YMMV.
Not bashing Benchmade , but having owned and used many different knives of each brand including a Large Inkosi and Bugout, in all my years of living in rural areas, hunting, camping, fishing, gardening, working with livestock, and farmers, and general EDC carry ... it would be an easy choice for me ... CRK Inkosi.
For posterity ... 1st pic are the sharp pointy tools I was carrying/using today (emphasis on using for those that think CRK knives are only for show) ... 2nd picture from earlier this summer shows the 21's wear better. Over 10 years of carry on the Sebenza hasn't hurt it at all. It's still as buttery smooth as the day it was broken in.
