Master, I've been using that sweet unit for years.  Alkalines run forever in it....any cheapo brand.  It's your use of the backlight that runs 'em dry.  I used my machine alot and I'll wager that 4 extra cheapo AA's in the pack...and you are good for over a week.  I've never had to change batteries once yet on a 5 day trip or less.  And all I ever use is the cheapest blue-light specials.

Was gonna upgrade to the 62...but saw a blowout price on a Colorado I couldn't pass up.