I have used all three and use CA on almost every wood pen that I make.
Enduro - very durable and can be buffed to a glass like shine although it does not enhance the color of the wood quite as much as the other two, very low odor, requires sanding/buffing to achieve smooth surface and high gloss, ease of application is same as CA but requires a couple of minutes for each coat to dry and requires several hours of curing time before it can be sanded/buffed, requires sealer and topcoat.
CA - very durable and can be buffed to a glass like shine, requires sanding/buffing to achieve smooth surface and high gloss, noticeable odor which some find offensive or irritating, steepest learning curve of the three but very easy once mastered, dries quickly (especially with the use of accelerator) and can be sanded/buffed immediately
Behlens - Not very durable, quickest to apply, does not require sanding/buffing (although I would recommend buffing lightly to remove rings around the pen), can achieve semi gloss with proper surface prep, but falls short of being able to produce a mirror like reflection of which the other two are capable, very distinct odor but not offensive or irritating, great for Christmas ornaments and small boxes
For pens, the finish that I use must be durable. After that, time required for application is the next criterion. So, that leaves me with CA as my finish of choice. I would choose any durable finish, regardless of time required, over Behlens or any friction polish. Durability is that important to me.