I actually used "Beyond Little Hearts..." with my second grader last year (and since I'm the author what follows is a slighty biased opinion
) but I will say that both my son and I thoroughly enjoyed it. We really did find that the age range was right on target for us. It also provided a great foundation for "Bigger Hearts..." which we are doing this year for third grade.
For "Beyond...", my son did the Level 2 spelling lists in the back of the guide, used the last half of the math lessons in "Beyond..." for Singapore 1B and then moved on to the Appendix schedule for Singapore 2A, and used "Drawn into the Heart of Reading" Level 2/3 with the more difficult books in the "Drawn into the Heart..." book packs.
He also was able to read all of the science selections himself, which he really loved (and I loved his growing independence). He read some of the history selections to himself (and could have read even more, except I wanted to keep that cuddle up and read time with me). He was able to copy all of the poems each week by doing a stanza or so each day and really ended up with a beautiful poetry notebook at the end of the year.
We found the once a week grammar lessons to be a short and sweet introduction to the more formal Rod and Staff grammar used in "Bigger...". The minimal writing required in "Beyond..." was a plus for us, and now my son is old enough to handle the stepped up writing required in "Bigger...".
Even my oldest son listened in and enjoyed the read-alouds from the Storytime" part of "Beyond..." last year, since we read them aloud at lunchtime.
If you have any more questions, feel free to ask. Perhaps, some of the other moms on this board will be able to share their wisdom in this area as well.
Have you gotten a chance to look at the placement chart on our site? That is the best way to tell which program will suit your son best. Here is the link: http://www.heartofdakota.com/placing-your-child.php