Sorry for late update. I signed (3) Korol and keep total 5 strikers for some time even though I usually use 1 or 2 strikers. Both (1) Damassceno & (3) Korol are quite fast trainers but do not perform well. Lastly, I decided to sell (3) Korol because of his approximately 25 sp disadvantage below (1) Damassceno.
(2) Francis has a quite good season, scored 14 or 15 goals in his career in my team, and trains quite well for a 25 year old player. I think keeping him is absolutely a right decision.