Im just gonna write a short note on why this is a good build. Its very easy, with the warmogs, 2 bloodthirsters and botrk you will have alot of damage, attackspeed AND hp, if you are also using the same runes, it means that with full build, elexir and baron buff you will have over 3000 hp and about 557 ad with lots of lifesteal, armor penetration and good attackspeed. You will have alot of damage while still being able to take som damage.

For summonerspells its situational, i like using teleport for strong farming and laning early and splitpushing and ganking mid/late game. Exhaust, ignite or barrier could be better alternatives for you and your way of playing.