Finally got the side by side of my last attempt I did splitting the batch with S-04 and S-05 (post #88 of this thread). Unfortunately I moved away from IL so don't have access to FFF's Zombie Dust anymore, but I am flying to Chicago in a few weeks, so will take some of mine with me to compare.
Here are some notes from my two:
-S-04 is a lot fruitier than the S-05. Peach/Mango/Apricot with a lot of citrus in the mix as well. S-05 has similar qualities, just not as much as the S-04
-S-05 is much more bitter tasting. The @-05 fermented out a few points lower, so that could be impacting this.
-S-04 is a bit sweeter, but definitely not overly sweet. I may add some crystal to the next one.
-S-04 cleared better (so far). I did not crash cool this, and only had it in the fridge about 10 hours prior to drinking though.
-The bitterness, color, and hopping are damn close. I may try upping the crystal, perhaps adding .25-.5 of Caramel 10 or 20 next time. I will probably wait until I try the real deal in a few weeks to decide on this for sure.
-next time I will not forget to pull the dryhops (went 14 days on accident, started to get a little grassy, but it is still very close). Next time I will do 7-10 days like the original batch, then do a second dry hop if needed.
So, as is right now, I think I prefer the S-04 and it is closer to the original. If you like more bitterness and crisp IPAs, S-05 would be more up your alley. The g/f really liked the S-04 due to it's fruitiness (she normally doesn't like ipas much, so that says something).
KobainIsAlive-
I considered using the 1968 since it is used in some other FFF "clones", but had a bunch of S-04 on hand and have seen it can be a replacement for 1968, albeit not an exact one. Let us know how it turns out. Maybe I'll do another split next time with it and S-04.
The FWH bitterness seems to be a debatable topic all over the boards. I don't know how many ibus it puts in, but do know it doesn't taste as bitter as a normal 60 minute addition. The bitterness is pretty close. Some of that could be that my hops lost some AA, they were about 6mo old. If I move the "20" FWH to 60, it only adds another 10 ibus. I think if I were to use the S-05 in the future, I may cut the ibus back some, but keep them close to the same with the S-04. Can you post up your hop schedule once you get to try it and let us know what you think?
I think yours is going to be good, but it will probably come in light in color. My first attempt was around 7.3 SRM and was lighter in a side by side with the original at the bar.