you don't need to be level 20+, but you do need to be well equipped. personally, i find an uppercut with a ballistic fist to be very effective. and if you plan to take on several at once, chems are very important.
armor really isn't as important, because i believe they hit through DT.
Hm. True. I think at level 14, with my character, I could take on a Deathclaw but apparently Boone and ED-E were picking them off like they were nothing. I should probably try after I get
I think that'll be enough if I play it out correctly.
Once you factor in a second Deathclaw, chems are pretty much required since with melee and unarmed, unless you're using Throwing Spears which completely just distorts the whole idea of rushing with melee and unarmed and someone else can elaborate on that, you can really only hit one at a time and have to wait for the animation to finish and all. Slayer makes this a bit less painful, or I can only assume considering http://www.gamesas.com/index.php?/topic/1146426-the-wording-of-unarmed-attacks-and-unarmed-weapons-in-perks/ is still around.
Or....
Paralyzing palm is for wusses.
No VATS.
No sneaking.
Rushing only.
Final destination..
This. Honestly, both work out perfectly well.