First Wort Hopping question

I am finalizing my recipe for my brewday today and I am going to do my first attempt at first wort hopping.

This will be an IPA, full boil, 7.24 gallons for a 5.25 gallon batch.

Grain Bill
10 lbs 2-Row
1 lb Biscuit
1 lb Caramel/Crystal 60
* I have DME available incase my efficiency is low

Hop additions
1.00 oz Citra FWH 60 min boil (30 min sparge) - 48.8 IBU (13.9 AAU)
.5 oz Citra 15 min boil - 10.3 IBU (13.9 AAU)
.5 oz Citra 10 min boil - 3.8 IBU (13.9 AAU)
.5 oz Citra 5 min boil - 2.1 IBU (13.9 AAU)
.5 oz Citra 1 min boil - .9 IBU (13.9 AAU)

This gives me 65.8 IBU on Beersmith where I am using the 60 Min Boil and First Wort Hop calculation. I have the input set at 90 to account for my sparge? Is this an accurate AAU calculation for First Wort Hopping?

I know there is a lot of debate on FWHing calculations to either put them in as I did or input them as a 20 minute boil. When I enter them as a 20 minute boil my IBU's go down to 42.1.

Which calculation should I use or should I just skip the FWH altogether?

Help?

This is tough because, from everything I've read, FWHing will yield more IBUs, as measured analytically, but the PERCEPTION is a smoother, less bitter beer, which is why some folks suggest treating it like a 20 min addition. I just did my own first FWHed beer - a German pils - and treated the FWH addition like a 90 minute addition (as suggested by Gordon Strong in Brewing Better Beer). The estimated IBUs for this beer is close to 40, but when I tasted the hydrometer sample the other day, I was struck by how NOT bitter it was. Still too early to say how it will end up, of course, but am leaning now towards treating the IBU contribution more like a 20 minute addition.

L

Im just going to go with my gut and do the 90 minute FWH on Beersmith and my hop schedule as posted.

I've abandoned the FWH technique myself, the bitterness you land up with is lower than your recipe will account for. I, personally, have found it too difficult to predict how bitter the beer will eventually taste.
The bitterness may be smoother, but hitting your numbers from a point of view of getting the balance of your beer right is difficult IMO.

I FWH a lot. I adjust it to be a 30 minute addition and it seems to work fine for me.

There's no simple answer, as there is a high degree of subjectivity in how people perceive bitterness. Personally, I treat FWHs as a 20 minute addition and find that I have no difficulty producing consistent beer at the level of bitterness I expect. Others I know and respect treat it like a 60 minute addition. It's just one of those things where you have to figure out how it tastes for you.