I’ve never used abeka but I just got in the masterbooks math and got to say I love it. The fun little stories and my son is obsessed with it and is asking to do it each day and then doesn’t want to stop. So if abeka isn’t working try masterbooks I got level 1 for my kindergartener for $25 on amazon so at least it’s an affordable option if you go on their website there’s like 30-50 pages to view of each book and a placement guide.
Iv'e used abeka and masterbooks math level 3. I've used masterbooks 3-6 and abeka for K, 1, 2, 3. I really like abekas workbooks they are spiral but build in a way that makes a lot of sense! I do not like that I have to order a homeschool curriculum guide and that everything is laid out using only the stuff from them and that can be expensive. I do not like all the extras there are with it, like drill sheets, tests, flashcards, and games that are incorporated into it. However it is a solid curriculum and been around for YEARS so I know its stood the test of time and as long as I'm willing to adjust what I do and do not like I can make it work.
Masterbooks was kind of a toss up for me. I LOVE it, its easy to use, easy to supplement if needed, it is inexpensive, and I love the stories! My older one who used it did well until level 5-6 it just didn't explain enough to understand the concept, also the answer key was so full of errors I never knew if he really got the answer wrong so I'd have to recalculate everything. But for level 3 he did so good with it and we both loved it! He did fly though it though and finish level 3 in 4 months. My next son did not do well, there simply wasn't enough repetition for him and he fell behind after using level 3 and 4, and there was no growth in understanding or concepts. I supplemented heavily for both boys.
I cannot say I would choose either. But I also really love them both in different ways so just telling my experience!
I used Abeka Books math for K5, 1, 2, 3 with my oldest and I have now used MB math for 1, 2, 3, 4, 5, and 6 more than once with a few different children.
I prefer MB. It is open & go, gentle yet solid. We go from MB 6 to Teaching Textbooks 8.
As with every curriculum, I tweak and adjust exactly what we do based on each child and our life circumstances, but overall, MB works great for our large-family life!