List of submarines by upgraded maximum stats

Advantages and disadvantages:

• Submarines can only be attacked at by destroyers, light cruisers, torpedo cruisers, and light aircraft carriers. In addition, they are prioritized to attack submarines first, meaning your other ships get away with no damage for free.
• Submarines are also the most resource-efficient class in the game, they cost almost nothing to deploy, and in addition the two or three expeditions you can send them on are very cheap because of this.
• If you have Type A Ko-hyoteki, you can put it on a submarine for extra attack before the shelling phase.  After you get a submarine to level 10, they'll have that initial attack without any equipment at all. You can replace the equipment with regular torpedoes or turbine to increase their low evasion.
• Once you level them up a bit you can take them to 2-3 and leave the stage as soon as you hit a fuel node.  Easy fuel.
• Imuya is the only submarine whose repair time doesn't double after remodeling.

Highlight note:

• Green: Outstanding
• Yellow: Above average

No.	Name	Class	Mod Lv
126	I-168 伊168改 Nicknamed Imuya	Kaidai 6a	50	11	69	0	0	29	10	15	18	49	Slow	0	10	20
127	I-58 伊58改 Nicknamed Goya	Type B3 (SSV)	50	12	84	0	0	39	50	18	19	49	Slow	2(1,1)	10	25
123	I-19 伊19改 Nicknamed Iku	Type B1 (SSV)	50	12	89	0	0	39	13	18	19	49	Slow	2(1,1)	10	25
128	I-8 伊8改 Nicknamed Hachi	Type J3 (SSV)	50	14	84	0	0	39	25	19	19	49	Slow	2(1,1)	10	25
155	I-401 伊401改	Sen Toku (SSV)	35	?	?	0	0	25	26	24	12	?	Slow	6(3,3)	?	?
163	Maruyu まるゆ改	Type 3 S.T.V.	20	2	2	0	0	4	7	7	4	13	Slow	0	?	?