Hi, I need good 24" range hood for my new kitchen and I'm looking at these range hoods: 1. STD-100 - Cost $259.00 but it has only a 600 cfm, how important is this? 2. KA-146 - I like it more, but price $919.00, it's very high 3. KA-144 - How about noise level on 940 CFM? Any advice would be welcome.