1) Handheld or fixed-mount? I sail on a very large mountain lake and could be 10 miles from aid, still line-of-sight.
I think you mean "as the crow flies?" Line-of-sight means, literally, line-of-sight. To give you an idea of what LOS really
is, here are some numbers:
Height of antenna: 6 ft ( 1.8 m)
VHF LOS to horizon: 3.0 nm ( 3.5 mi, 5.6 km)
Height of antenna: 40 ft (12.2 m)
VHF LOS to horizon: 7.8 nm ( 8.9 mi, 14.4 km)
Naturally, LOS is "additive," and you're rarely trying to communicate with somebody sitting in the water in an inner-tube
Height of antenna #1: 6 ft ( 1.8 m)
Height of antenna #2: 40 ft (12.2 m)
VHF LOS between antennas: 10.8 nm (12.4 mi, 20.0 km)
So, as you can see, height is important. As for hand-held vs. fixed mount: A fixed mount is going to have more transmit power and more sensitive receiver.
2) Brands to shoot for, brands to avoid? Looking for ease of use and decent sound quality, not lowest price.
I plan on either a Standard Horizon Quest-X GX1500S or an Icom 402 or 422, for the following reasons:
- Somebody a couple years ago evaluated the receive audio quality of everything on the market and found these two beat all the rest far and away. This is an important quality.
- Both have the ability to accept a remote access mic (RAM). That way we can have the radio mounted below, and still hear and control it from the cockpit.
- Both can be interfaced with our Garmin GPS so we have one-button MOB/distress capability
3) Features that are worth considering?
See above. There are others. I'd read the owner's manuals on-line to see how they're operated before making a choice. I did that for the radios listed above, but it's been so long I forgot which one I preferred! One of them clearly had a more useful operating system, IMO, tho. (I think it was the SH, but I'm not certain.)