Hi Mammamo!

(Does that username mean you live in MO?)
I used RS this year with Little Hearts and it will work for you. I, too, love RS, and I truly feel it is an awesome math program! Some of the activities in the math block will go with RS, you'll just have to look ahead and match up the topics.
I tried to use MUS after RS A, and while I feel that it is a great math program as well, my kiddos balked at the workbook pages (since you use RS, you know that there are almost no worksheets so the redundance of those MUS pages kinda got to 'em.)
I just last week started with Singapore 1A and so far have been very pleased it and, more importantly, my kids are enjoying math again. I plan to purchase the RS games kit to go along with Singapore since the games (for us) were the most fun part of the curriculum. My manipulatives are also getting a good workout as those can be used with any curriculum.
For me, it was a matter of wanting to open up the HOD guides and go for our whole day. I guess I've been slow to come around

b/c I started HOD with RS math and LLATL for phonics/reading. Next year, we will be a total HOD family!! I always try to give new moms that warning, you may become hooked once you start on HOD!!!
