The problem with the series is that all but 13 episodes fell into the public domain. So that pretty much rules out a legitimate release from the negatives. I haven't seen the Alpha discs but from what I heard they look like VHS dubs. The package VCI put out a while back is actually pretty decent quality considering. I would recommend that although its only about 12 episodes. Alpha and some other company that put out the show even have an episode that's not even from the series, which shows you how familiar they are with the product.
I have the 12 DVD set. Although the stories are excellent the quality of the episodes are not the best. I t however was worth the $4.00 per disc price. (You can buy the discs individually or in the 12 DVD set)