I did Manhattan Prep the first time. It is the gold standard. It is really pricy but is really great if you want a decent score without putting in too much work because class is facetime with the teacher. I scored 650. You need to self-study which could be difficult since there's no structure besides doing the homework.
Economist GMAT is what I used the second time. 720. I find it way more comprehensive, teach you a lot of neat tricks. I put in a lot more work and just follow the web app. The app is great, it gives you instant feedback and focus on your weak points.
https://learn.gmat.economist.com/