I guess it's about your prioriites. If sex isn't a high priority in your life, then sexual compatibility with your partner won't matter much. If it's a high priority for either your OR your partner, then you'd be wise to make sure you're on the same sexual page before you legally bind yourselves together.
I guess that's the real question: How does (a) whether or not a couple sleeps together before marriage correlate with (b) how successful the marriage is.
I haven't carefully screened these sources, but it sounds like premarital sex may by positively correlated with higher divorce rates:
Although the correlation may be weakening over time:
This suggests that premarital promiscuity is bad for marriages:
But given that website's ideological viewpoint, I would wonder if they were selective in their sourcing.