No ante's per se. You could fold. If you were first to act, and stayed in, lyou had lead out with the min bet for that round. Very few people folded for the $1 pre-flop bet, so while it wasn't an ante, it pretty much worked that way. But very few people folded $2 second round either. You're playing with a LOT of cards.
We played 3 rounds of this over the night, so I played 21 hands, and I can't say I'm an expert.
Yes one difference is cost, but the other difference is what you end up with as far as hole cards. With "Ray" you pay $5, (and get the new card), but you discard one card from your hand before you get the new card, so you end up with only 6 hole cards. With "death ray" you pay $10, get a new card, but end up will 7 hole cards.
From what I saw last night, if you haven't folded by that time, it almost always was worth it to get either Ray or Death Ray. Standing pat to save the $5 into a $100 pot didn't seem +EV.
Whether you got the card and which one you chose was based on the texture of your hand (your playing both low and high hands, playing one side only from your down cards, etc..) could cause you to want to pay $10 for the death ray to keep all your cards. The majority of the time you had a disposable card under that allowed you to cheap out to pay $5 for the extra card and discard the disposable card.