Hi Dark,
I would say the pros are: the ss5 6f/4r torps (big punch, if you hit) and the possibility of carrying enough bulge to take a punch and live to tell it :P
The cons are the big percentage of duds for all tiers (sometimes a whole "salvo", e.g. the 6 front torps are all duds, so it is better if you play at max range) and the poor turning force.

I think its a good sub line, you will enjoy it :) 

Best regards,

Ade 

pro = easy to level crew ona aCV /BB

con = its not km

KM subs aren't all mighty gods you know.

As for the USNS SS5, As said before, it packs a punch, if the torps don't dud. 

Pro: It might end up faster than your Montana.

Con: Probably not.

The worst thing about USN SS is that they have a crazy high dud torp rate. Its very frustrating to see most of your torps go through your target.

Not sure if it is me but I feel that critical dive is a bit slow. Right when I see PHH come out of the guns, it does not matter if you critical dive right away, you get sunk instantly.

i have noticed this too. i know it has been said many times how it is 3 second dive on all subs. i can imagine this being another one of the misleading stats.

I have no problem diving under thing with my km SS's but the US SS's seem to catch torps and HH right before the are fully down.

I can imagine that all subs dive at 3 seconds but i am betting there is more to the story like.

KM dives at 3.1 sec

US dives at 3.6 sec

(these are geustimates for example only. I have done no testing other than gameplay feel.)

still in the same vague answers all over these forums. "all subs dive at the same rate, 3 sec.".