it's the only portable one - retails for around $250, so it's a bit pricier than others, but it's very versatile, can use in car, home stereo, and walking. can also record content, so if you don't get good reception traveling you can listen to your pre-recorded content

it's about $12 a month for subscription.

as far as safety: discussed in many other posts. personally i use a small earpeice on my right ear. i wouldn't recommend the plug type, or noise cancellation, as it would get rid of car noise. (which you don't want)- just the "earphone" type which sits in your ear or hangs over ear

if someone feels unsafe with it i wouldn't recommend, but given the fact many motorists are completely sealed with blaring music in cars, for myself i don't think listening at a reasonable volume in the "curb facing" ear is unsafe (at least of me)