The difference between a SR scrapper and a SR brute?

I have a Katana/SR at 32, but I've got a question. Is a brute in general more suited towards super reflexes? It seems like it would be easier to softcap, and allow my primary to thrive, but surely Scrappers have some ups, as well as downs. And I'm lost on it.
So, what's the difference between a scrapper and a brute with the same build?

Base values are identical.
Scaling resists in the passives are identical.
No easier to softcap one over the other.

Brutes have higher base hit points get more out of the scaling resists because of it.
Brute evasion has a taunt aura.
Brute SR power order makes more sense but getting quickness so much later in the build can be a downer.

And Brutes have a higher damage cap and get Fury.

And brutes do significantly less damage with most primaries ceteris paribus. SS is an exception as scrappers do not, and never will, get it. Katana is not an exception because scrappers do get it and it benefits from scrappers' radically superior build up, musculature, assault, enhanced critical values, and so on.

I made a brute clone of my kat/SR build to compare their numbers. Since mid's does not have ATO's yet though numbers can be change but from current point on same choices or closer ones (my scrapper kat/SR have body mastery but brutes don't get it so I put energy mastery instead which was closest).

I assume both builds have purple ATO placed on soaring dragon.

Both build have softcap positional (ATO's set bonuses are same) and with one small purple both can get to incarnate softcap. %15.62 res to s/l (with ATO), %177.5 global recharge (again with ATO) and %33 global damage bonus (again with ATO)

Brute has 116.8% max end while scrapper has only 111.8% (because of difference between conserve power and superior conditioning) both has %219 recovery but scrappers is actually 4.08 end/s while brutes is 4.26 end/s.) Also scrapper has only two performance shifter proc slotted while brute has three (again because of difference between superior conditioning and conserve power)

Scrapper's Golden Dragonfly's per animation damage is 222.5 (ATO crit chance increase as well %3 global damage bonus doesn't included since mids still doesn't have it and I don't know how it may effect GD)

Brutes Golden Dragonfly does 205.8 damage with %80 fury (ATO doesn't included in here as well).

Asuuming that build up was up scrapper's GD does 305.4 damage while brute GD only does
244.3.

Assuming that gaussian's build up proc fired up together with build up (rare but I saw this happening a few times) scrappers damage is 388.2 while brute's damage is 282.7.

With %100 furry (brute ATO AFAIK lets brutes to get to %100 furry) brutes damage is 225. With only one build up this increase to 263.5 and with both build up its 301.9.

A point on damage to keep in mind; Mids calculate chance of critical in its calculations so the damage with build up's may not end up as how its calculated on an avarage scale.

To sum up what's already been said, and add my 2 Inf:

1- Brutes and Scrappers get identical base Defense and Resists. Brutes have higher resist caps, but no SR is going to get close to the resist cap without outside buffs or inspirations.
2- Brutes and Scrappers have identical base Regen and Heals. However, both are based off your HP total, and Brutes have higher base and cap. Therefore, Brutes can survive the hits that get through better, regen those hits faster, and (if they take Aid Self) heal themselves for more.
3- Brutes have the lowest base damage in the game. Average levels of Fury will put a Brute and Scrapper at even damage levels based on SO slotting and no buffs. Damage buffs are based off base damage, so the same buff gives a bigger boost to the Scrapper. On top of that, Scrappers have a higher buff scalar than brutes, so they get a bigger bonus than Brutes. For example, Scrapper Build Up adds 100% to their base 1.125 damage, where Brutes add 80% to their base 0.8 damage, meaning that a scale 1 attack performed with Build Up in effect deals scale 1.44 damage on a Brute and scale 2.25 damage on a Scrapper.
4- Most Legacy power sets that get Proliferated get long-standing issues tweaked, but if the tweaks involve reordering the powers, only the new AT(s) get reordered. Brutes are the newcomers in this case, so they get the better power order, and have all their most important powers by level 20. Waiting for Quickness is a drag, but far better than waiting for your AoE defense. Katana isn't going to lose much by waiting for Quickness anyways.
5- (Not applicable to Kat/SR) Damage auras Are an exception to #3 above - they're better in a Brute's hands.

Short version:
Kat/SR Scrapper does more damage, faster, and at a consistant amount. They are weak to AoE attacks for over half the leveling process.
Kat/SR Brute does less damage, and has to ramp up to it, and is slower for a good chunk of the middle levels. However, they have solid defenses to all positions before they get SOs, and survive better on equivalent slotting.

SR Scrappers get Quickness at level 20, Brutes at level 35.

SR Scrappers get Evasion at 35, Brutes at level 20(Brute version also functions as an Aggro Aura; detoggles if mezzed).

... There's a speed slower than killmaimpillage? I go the same speed on all my brutes and scrappers.

To expand on what I said, beyond the slight advantage many scrapper sets tend to get by themselves due to crits, in my opinion the biggest factor for a "neutral" set like katana is whether you want to use musculature or a different alpha. Musculature is great for scrappers but a fair bit less great for brutes. Specifically, brute tier 4 musculature is going to do not quite twice as much for you as scrapper assault, and one of those things takes up your alpha slot. Obviously not every build stands to benefit more from musculature than from other things in the first place so your mileage may vary.

For many, Brutes doing a bit less damage than Scrappers (which if I'm not mistaken, Scrappers win in the damage department with this combo), is more than made up with an aggro aura (though I have no idea how good SR's is, it's still more than nothing) to keep themselves surrounded and not chasing after enemies and higher survival, which in this case is just a matter of extra HP and the extra regen that gives.

Note however, this is going the solo route. And outside of a few minutes of staying at the damaage cap by downing a bunch of reds, having a higher damage cap means nothing if you can't reach it solo.