arm thrust is lackbuster really since its a 15 powered move wich ecomes 75 on 5 hits which is pathetic i prefer to loose the defense than having to take several hits
I'm sorry, but I just can't follow that logic at all. You're okay with losing defensive boosts on a defensive boosting set? Close Combat is for pokes that are fast and frail and thus don't really have to be concerned about taking hits. And with only base 75 speed, you WILL be taking hits from offensive pokes, guaranteed, whether you want to or not. To compromise Megacross' otherwise solid defenses is suicide, and in even the best case scenario you'll be forced out and the attack boosts you've accrued will be wasted.
And yes, while Arm Thrust is a hell of a lot weaker than CC, is that really going to matter when you have a base 185 attack stat that's also boosted by Bulk Up on top of that? Conkeldurr has no problem using Drain Punch, which is also a base 75 power move, as its primary STAB, and he's "only" base 140 in comparison. He has no problem crushing most of the tier at +1 with that. You never see BU Conkeldurr using Superpower, even though that's base 120, because it discards the boosts that you worked so hard to accumulate.
To be honest, I see CC on Megacross as being a bad option on any set other than a bulky 4-attacks set that attacks off the bat with no setup and then immediately switches out. With no Scarf, and reduced speed, while it will usually kill the opponent, it will also leave you prone to being revenge killed. Megacross has strong bulk. Play according to that strength, not that of regular Heracross, who is faster and can also hold a Scarf.