Should I combine a Reborn Wand of Doom and a Freezewand of Doom to make a Reborn Icewand of Doom? Is it worth it?

That depends on how much you pay for those two weapons. If it is cheaper than like the 25m it is for the RIWoD, then go for it. If not, then I would just buy the combined weapon.

I personally have one and love it. Multi-use, 10-14% heal, chance of freeze and both blocks and does a bit of damage. Combine if you can make it cheaper that way or need the achievement, but I love the weapon.

Yeah, I would definitely get it. Get it which ever way is cheaper. I have LOVED mine ever since I got it :D

get it, I love mine, have loved it for a while