Apart from the odd terrorist attack Hezbollah has always fought on the defensive against Israel. In Syria they are having to go on the attack in open country, That is the kind of warfare that tends to turn on logistics, not zeal.
As for the Iranians, it's been 25 years since they fought a war.
The Iranians killed hundreds of US troops in Iraq with their IEDs. They can literally throw battalions of suicidal islsmists at anyone they want. And they lost generals to sucidal spy attacks. Agree with the other poster. This is not good news for the region. My 2 cents - Order your Iodide tablets now.