Go with the Marlin, hands down. It has numerous advantages over the Winchester. Most notable being a SAFETY! Which for some odd reason, the Winchester lacks. You get someone in the field whohas cold, small, or weakfingerswith a cocked 30-30 and no safety, you're just asking for trouble when they put the hammer down. Secondly, the Marlin has side ejection, versus the Winchesters top. I'd actually been smacked by a Winchester top flying shell, never with a Marlin though. And this is personal preference, but I think the Marlin just looks nicer. This is a moot point though.

If I was you, I'd go with the Marlin. If you plan on letting kids use this now or someday in the future, you'll be glad you picked the Marlin. I've seen people's fingers slip off the hammer time and again when decocking the gun. Go with the gun that has a safety.