What do you guys think about this build? ^^

25SPR/25DEX/Rest-STR

25SPR - Additional 5% crit
25DEX - Additional 5% evasion 10.5% aim (or the other way, I can't exactly remember. Correct me if I am wrong)
Rest-STR - You all know what's STR for. xD

Ok. Well, let's not mention END because I used to be a END/SPR Tank.
Shortly after hearing a few opinions from friends, I decided to re-stat and switch to STR/SPR instead. I realised that, there is no significant changes in my defense at all. 50END points only adds about... 25 Defense and 250 HP. -_-;; Ok. As a level 79 tanker... What's the point of additional 25 Defense and 250 HP. ._.

Adding STR however, allows me to kill faster. At free stats, I realised that, there is a bonus damage increase at every 5 stat points. And in killing and damage wise, there is a significant increase in the speed of killing. (When soloing of course)

So over here, I have two question.
One is... 25SPR/25DEX/Rest-STR... What do you all think about this build o.o?
Second thing is... What's the point of adding END on stat build? ._.