It looks like a few people use it with beer, even though it is more associated with wine. Every mention indicates that it is used in secondary only. Sparkolloid carries a positive charge and yeast is negative, so it will speed up the flocculation of yeast. Because it is used for removing yeast haze I would suspect it would at least lengthen the time required for bottle conditioning. Another consideration is that the manufacturer recommends allowing 30 days and up to 8 weeks after use to avoid bottle precipitation.
I collected a couple links from around this site, since I am curious about this too (I ordered a bunch accidentally and was thinking of trying the extra in some beers).
If I use it I'll report back my experience.
Using sparkolloid in beer: