Whether it's a good thing or a bad thing depends upon how you feel about the strategy of offering books for free.
When I first started, there were people who claimed to have built their careers on strategic use of free days. As time went on, the device declined in effective because of the ever-growing number of free books available, but some people have still gotten good results. However, those contemporary successes are from people getting good sell-through on subsequent books in the series.
Since this is the first in a series, you obviously won't get sell-through. And it takes a lot of freebies to get any reviews, if that's your goal. So the argument could be made that it's not the best strategy.
That said, I know people who would argue for it as a way of getting recognition early on. If enough of the downloaders actually read the book, that could be true. There's an active debate on how many freebie downloaders really read what they download.
But if the strategy is effective, it relies for that effect on volume. So, if you believe in it, you want there to be as many free downloads as possible. On the other hand, if you worry you are losing sales by giving it away for free, then you probably shouldn't go down that freebie road at all.