I refuse to use cordless rotary hammer drills.
People reckon they're the ducks guts, but I just see a tool that's not as good as it's corded counterpart at doing anything.
Show me a cordless rotary hammer that can core a 75mm hole through a 200mm steel reinforced slab.
This is true, but they do come in handy when your in tight spaces with limited access to power and just need to drill a few holes in brick/concrete, I guess the biggest bit I'd use on a cordless is around a 10mm, anything over that and I'd want the power of my corded beast.
I used my corded one to drill a few holes yesterday with a 6.5 bit into brick, it just seemed so excessive for such a small drill bit.