Aroma hops for Imperial Stout

I'm thinking of brewing NB's Imperial Stout very soon to have it ready by Christmas. I see it uses Summit for bittering...and Cascade for aroma. I always like to try new hops/grains whever I can, so I'm wondering what would be a good alternative to Cascade for an aroma hop in an Imperial Stout?

Horizon? Glacier?

Thoughts?

I was just looking through the listings of hops I've never used and had an idea. What if we took the NB Imperial Stout recipe and used only Horizon hops for bittering and finishing? I'm thinking if I bump up the 60 min addition to 3 oz of Horizon, then use 2 oz of Horizon at flameout the IBUs would be roughly the same as the stock recipe.

Anyone used Horizon before? Thoughts on this change to teh recipe?

ive never used horizon.you can use goldings for aroma. but hops arent very noticeably in an imperial stout

magnum is good smooth bittering for stouts. IMO northern brewer is good too. ive only used summit for bittering in an IIPA and it was great

I, also, have never used Horizon before, but came across a blog post by Michael Dawson of NB extolling the virtues of this little known hop. He says it was very clean and neutral bittering properties and the aroma is a mix of lemon/citrus with some grassy notes. It is a dual purpose hop and if I can get my hands on some, the plan is to brew the Imperial Stout with just Horizon acting as a dual purpose hop.

I'll follow up in several months with how it turns out!

I don't use aroma hops in a RIS. IMO, there's no point.

First of all, you have to use an ungodly amt of hops to be detectable over the massive roasty malty aroma; secondly, by the time the RIS is mellowed and ready to drink (months) the aroma hops have faded and aren't detectable any longer.

If you are bound to go for aroma hops, though, I'd suggest adding them post fermentation, in a keg; or if bottling, add them to the last two weeks of your fermentation (in the carboy).