Definitely Flexzilla. I've swapped all the hoses in the shop over now. The cheapos that came with our cheapo reels lasted a couple months before all 4 had split at the fitting. I hacked them together with barb fittings until that got old. Of the 3 remaining, 2 got Flexzilla, one got Goodyear rubber. Just last week the Goodyear, at about a year old (and more expensive) split at the end too.
I'd get a 3/8x50. It's so flexible the length is easily managed. Whatever you do, don't try running your impact off the coil hose, except for your own entertainment... it probably wouldn't loosen an oil drain plug.