a. asserting Hieron is Askren's best win shows how little you know about the fighters Askren is facing. Hieron was the third best guy in his tournament. The majority thought he should have lost to Hawn, who the majority thought should have lost to Good. Good was probably the best guy in Hieron's tournament. And a couple tourneys later Good went on to lose to Koreshkov, who then Askren wiped the floor with. Really, Askren's best win is Lima. He's beaten everyone in Bellator, convincingly, but Askren. More realistically, Hieron was Askren's 3rd best win.
b. you realize it's commonplace to rank fighters in the top 10, without them having beaten a top 10 fighter, right? They have to rank 10 guys in the top 10, and they can't go back to 2007 to find someone with a win over a top 10 at the time, to do it. Jim Miller got ranked top 5 with his best wins being decisions over Tibau and Lauzon. The same was the case with Bisping, only decisioning the likes of Stann, Belcher, etc. So what's the big deal about Askren being in the top 10? Realistically, beating Lima is more impressive than anything Miller or Bisping did to get in the top 5.