I agree with both of you that there are lots of math programs out there. Your child won't be ruined as long as you work on his math skills consistently. But like Crystal, I've used several programs and I do feel Singapore's worth the effort. I mean, I think it's logical that you question whether something's overrated, but I want to weigh in on the "no" answer to that question
My son has taken standardized tests every year from 3rd to 8th. I sometimes have helped give the tests to some of the younger grades. One section of the math test is on drill and one is more thinking problems. When it comes to the thinking problems, I personally have the belief that I can identify kids who use Singapore by the way they jump right in. I could be wrong, but that's my personal view
As I read through your post, I just have some random thoughts. If you have more particular questions about specific problems in Singapore, I'm sure we could help you tackle those, too.
1. Math is going to have bumps in the road. As another mom told my son recently, "If you're able to whiz through your Algebra lesson in less than an hour, then you're not working at a hard enough level of math for you." Now, I'm not a big pusher, and ds doesn't always spend an hour on math, but the idea is that it's got to be a little hard sometimes in order to make significant progress.
2. Each child is different, but my son often gets overwhelmed with a new math concept. It just takes time to sink in. Eventually, I know he'll say it's "way easy," but at first he just needs to "dwell" for a while. When he was younger, I would pause by doing things such as using a second math program or focusing on drill for a while (both of which you've done, as well). Sometimes when he was on pause, I'd throw in one "hard" problem each day; sometimes I wouldn't. Sometimes I'd wait until he expressed an interest in going back to the main program; sometimes I'd just decide it's time for him to get going. Honestly, he still does this in 8th grade with some of the "big" Algebra concepts. But I'm so grateful that we homeschool, because by doing this, my very non-competitive youngest son has really excelled. He tests well and has even done well in some math competitions this year.
3. Singapore math, and math in general, builds upon itself. In the younger years, there are going to be some things the kids don't completely "get" or things they forget. There is even going to be a problem or two that's thrown in as a challenge for the kids who are ready. I know those kinds of things put me off balance at first, but now I see that I shouldn't have worried about every last detail. By about level 5 in Singapore, kids will be applying all of their skills often.
4. The biggest thing to me in Singapore levels 1-4 is exposure. Even if you just use it as a supplement by talking through the workbook pictures in levels 1-4, I think it has benefit. It's not until late in level 4 or definitely level 5 that you really "must" use the Singapore techniques in order to solve problems. Before that, you expose the child but often he doesn't really need to "use" the techniques to get the answers. By the way, don't press your child to use any particular technique in solving problems. The idea with Singapore is that there are many techniques. At some point, the child will recognize that he needs to dig out a different tool because otherwise he can't solve the problem
5. Like another thread was mentioning today, the reviews in the textbook can be done together -- orally or on a marker board. I found those to be an opportunity to "watch my child think." Remember when the classroom teacher had different kids come up to the blackboard? That's when the teacher can see what needs more teaching. The child may be understanding everything except one tiny piece of the puzzle and when that is put in place, "Voila! I think he's got it!"
Well, I can never be brief. I hope something in there is helpful