My all time favorite lift is the deadlift, and I often wonder if it would be worth it to find me a gym to get back at deadlifting heavy again. But most strength gained with barbells is 'gym' strength, it didn't make much of a difference outside the gym, for me at least.
Same experience for me.
DL is by far my favorite barbell lift although I think it doesn't really matter whether it's conventional or sumo, barbell or trap bar. The feeling of pulling a heavy weight from a dead start is very unique and special. I don't get a similar feeling of accomplishment through squats, bench pressing or whatever, no matter how heavy you load them up.
Getting stronger in the basic barbell lifts certainly increased my ability outside of the gym a lot, but I have at least to some degree have to say that I share Shawn's experience that a good amount of the strength you gain is "gym strength".
I already said this in the "barbell strength carryover"-thread, but working with KBs in some weird way unlocked my strength for the real world outside the gym and I experienced big time WTH effects.
They connected me in a way barbells never could.
There is still the obvious benefit for barbells that they are the best and most time efficient tool for absolut strength.
I could write a paper on the differences, benefits and my theories for barbells and KBs, but I won't comment further on the pros and cons for both implements, because it's all very specific from person to person.
For example I just talked about my personal experience that KBs had a better carryover to the real world than barbells, but I worked with barbells first and only after that concentrated on KBs. It may have gone completely different if I had started with KBs and worked with barbells afterwards or would have gone with calisthenics for 1 or 2 years.
Take a person who starts with KBs, goes on to achieve Sinister, complete the RoP, then RotK and then spends years training with calisthenics until he/she achieves very advanced bodyweight skills. After all that this person finally starts to use barbells.
This person will report about very different pros & cons for barbells and KBs then someone who's never trained before, used barbells as his/her first training tool and only tries out KBs after years of pure barbell training.