Blagoi Ivanov came into the mma spotlight when he beat Fedor in Sambo five years ago.since then, he was stabbed and nearly died. It's baffling that he was on the undercard last time he appeared on Bellator. Although, that last appearance was impressive with a quick guillotine choke. He also holds wins over Ricoo Rodriguez and Pride veteran Fujita. He is only 26 years old and undefeated in mma. Ivanov is most likely the best HW in Bellator. HIs reach is 73 inches and he's only 5' 11" tall. However, weighing 240lbs. he's built like a fire plug and hits hard. Coming in at a close second in bellator's HW division is Vitaly Minakov. He holds victories over Fabanio Scherner and Eddie Sanchez. Two fighters who were on the wrong side of highlight reel kos in UFC. Sanchez being a Crocop can and Scherner falling to HW Brandon Vera back when the mma community thought he might be a world beater. MMA fans generally consider that "you're only as good as your last fight". In Minakov's case, that's not very good. Minakov was dropping his hands in his last fight, seemed to be tired too early, and had difficulty taking down Ryan Martinez who isn't exactly known for his wrestling. Minakov is four inches taller than Ivanov but has less reach at only 70". The champion, Alexander Volkhov, is a fairly proficient striker with a karate background. Mma being the desultory sport it is, don't be surprised if Volkhov holds on to the title despite having below average grappling. That is if he learns to maintain distance.
I doubt Check Kongo has the mma wrestling/grappling to beat Minakov or Ivanov. Minakov might have had trouble taking Ryan Martinez down. This does not mean Kongo can take down Minakov. Still, Kongo may be able to outstrike Minakov and Ivanov. Volkhov's striking seems to be tighter than Kongo's. Although, I doubt Kongo would try to strike with him. Personally, I would like to see Kharitonov and a heavyweight Rampage thrown into the mix. All in all, HW in Bellator looks to have some intriguing match ups.