AG#8 My first dry hop

[Underground Joe]

I thought that it was about time to play about with dry hopping. I have come up with the following recipe in order to create a bit of space in my freezer. I'm confident this will make very nice beer at the darker end of an American IPA, but I'm after some feedback on dry hopping quantities as this is new ground to me.

Recipe specifics:

Style: American IPA
Batch size: 45.0 l
OG: 1.056
FG: 1.014
Bitterness (IBU): 57.0
Color (SRM): 14.7
ABV: 5.6%

Grain/Sugars:

9.00 kg Maris Otter Malt, 76.6%
1.00 kg Wheat (US), 8.5%
1.00 kg Munich (US), 8.5%
0.75 kg Crystal 150L, 6.4%

Hops:

30.00 g Simcoe (AA 14.2%, Whole) 60 min, 20.3 IBU
30.00 g Amarillo (AA 10.0%, Whole) 15 min, 7.1 IBU
30.00 g Simcoe (AA 14.2%, Whole) 15 min, 10.1 IBU
30.00 g Amarillo (AA 10.0%, Whole) 10 min, 5.2 IBU
30.00 g Simcoe (AA 14.2%, Whole) 10 min, 7.4 IBU
30.00 g Amarillo (AA 10.0%, Whole) 5 min, 2.9 IBU
30.00 g Simcoe (AA 14.2%, Whole) 5 min, 4.1 IBU
30.00 g Amarillo (AA 10.0%, Whole) 0 min, 0.0 IBU
30.00 g Simcoe (AA 14.2%, Whole) 0 min, 0.0 IBU
30.00 g Amarillo (AA 10.0%, Whole) dry hop
30.00 g Simcoe (AA 14.2%, Whole) dry hop

Yeast/Misc:

Irish Moss, 1.0 unit(s), Fining , boil 10 min
US-05 Yeast, 1.0 unit(s), Other 

[killer]

Nice looking recipe.
I've dry-hopped my last 5 batches of beer and people do comment on how perfumey it is (course they are all french people and not used to decent beer !)
Many on here and other fora recommend up to 4 - 6 grams of hops per Litre of beer. I've only ever gone up to 2 grams per Litre with noticable effects that I was very happy with.
I think for your first go you have the right quantity - it's a good starting point and you can always add more next time.