Help with 'Hop Showcase' Experiment

[LeSinge]

Now that New Zealand hops have arrived at my fav hop store I wanted to make a Master Batch of wort (based loosely off the Mikkeller Hop Series) and split it into 4 2.5Gal batches to compare/contrast with Cascade.
I went through Beersmith to figure the IBUs to get them close at 60 and 20 minutes.
As I added the identical amounts for each 0 min and dry hop addition I thought maybe I should look again at the amounts at 20 min.
How much difference in flavor influence will I have with the following?
Should I just rework the recipes to have the same amounts at 20, 0 and dry?
IBUs for each batch are right around 68
OG ~ 1.070

Ingredients:
------------
Amt Name %
9# Pale Malt 35.2 %
7.5# Pilsen 29.3 %
12 oz Pilsen Belgian 2.9 %
2# Caraamber 7.8 %
5 oz Caramel Malt 40L 1.2 %
2# Munich 10L 7.8 %
4# DME, Extra Light 15.6 %


Amt Name IBU
0.95 oz Cascade [6.10 %] - Boil 60 min 8.8 IBUs
1.90 oz Cascade [6.10 %] - Boil 20 min 10.6 IBUs


0.50 oz Nelson Sauvin [11.50 %] - Boil 60 min 8.7 IBUs
1.00 oz Nelson Sauvin [11.50 %] - Boil 20 min 10.6 IBUs


0.40 oz Pacific Gem [15.10 %] - Boil 60 min 9.2 IBUs
0.75 oz Pacific Gem [15.10 %] - Boil 20 min 10.4 IBUs


1.00 oz Pacifica [6.10 %] - Boil 60 min 9.2 IBUs
1.75 oz Pacifica [6.10 %] - Boil 20 min 9.8 IBUs

with .25 oz at 0 min and 1 oz dryhops/3 days


Thanks in advance for any input.
Have any of you folks done anything similar? Comments/suggestions?

[DragonOrta]

I would do same amount at 20, and just adjust the 60 min to get target IBUs.

[LeSinge]

I would do same amount at 20, and just adjust the 60 min to get target IBUs.

yeah, that's what I did..but I think I will need to further adjust the recipes due to the differences of the intensity of the hops...we'll see.
Fun Fun project, my nose and palette are still reeling from all the unique flavors and aromas flying around.