Re: battenkill mid arbor
The BLA III will handle steelhead in the water you describe, but the BLA IV would be a better pick. The larger backing capacity could come in handy at another place, but the bigger advantage is just the little bit overall larger size of the reel. In cold weather you'll appreciate the how easier it is to manipulate things that are just a bit bigger.
As Frank mentioned, if the BLA III is a must have, then you could go to gel spun backing or one of the braids, like Cortland's Masterbraid, but the extra expense of the backing would probably bring you to the BLA IV price anyway.
"If people don't occasionally walk away from you shaking their heads, you're doing something wrong." John Gierach