To me, the more frequent exchange is worth it. I was frustrated enough with the stock fluid to stick with the cocktail for 3 years. I bought the car to enjoy it. I bought a 5-speed because I enjoyed shifting. If I have to change the transmission fluid more often, then I'm up for it.
I just spent $50 on Amsoil Severe Gear 75-90, and it's not good enough. I'll be going back to the cocktail, or something else that "works" better.