I love Sam Adams Octoberfest. It's a great beer and I look forward to having one every Fall. Sam Adams is more expensive than some of the other beer I drink but I think it's worth it. They are one of my favorite breweries.
Depends on what you mean by economical. I think it might be a buck or two more expensive than your standard Bud or Bud Light twelve pack. (At least in NY). Even though it is a seasonal beer, it still is Sam Adams, so it's not as expensive as a microbrew or specialty beers. All that said, it's yummy, so definitely worth a try.