Firmly in the 600s to a 720. For what it's worth:

I walked out with a 720 (Q47 V42). I'm generally a lurker and this forum has been very helpful, so here's the crux of how I turned it around.

TL;DR

Native English speaker who thought he was "good" at math but realized that the GMAT isn't about that — it's about quantitative reasoning, which is what the section is labeled ??‍♂

The potent mix for quant was Target Test Prep and reviewing mock exams with gmatclub

For verbal, OG Practice Problems (online) and GMAT Ninja Videos

For what it's worth:

Using only the Manhattan books with what I now realize was casual studying, I got a 680 (Q39 V44) with what you can see is a poor quant score. I ran out of time on quant and was penalized. I thought the GMAT would be relatively simple compared to the CFA, but really it's apples and oranges. It's tempting to white knuckle your way through the quant with tons of algebra and without a calculator, but for most problems, that's just not how it works. I took the test again a few weeks later but there was no improvement. Clearly I needed help with math.

I discovered Target Test Prep through this sub, and I'm happy to endorse the work that Scott, Jeff and the rest of their team have done with the platform. Rather than piecing my way through books, it was much more effective to use an integrated, online interface where you could learn the content and do practice problems. Everyone will advise that you track your progress and keep an error log, and TTP basically does this for you. If you're limited on time, I think you'll see a solid improvement with just the easy/medium problems. I will say, though, that having drilled their hard problems, I consistently got Q48/Q49 in my mocks. The math felt relatively simple — at that point, my inefficiencies were more about test-taking skills and falling for the GMAT's tricks rather than a gap in knowledge.

As for verbal, I think Manhattan will give a great base. However, I'm a native English speaker with relatively decent language skills, so I'm not sure I got more of an advantage from Manhattan than I would have from just going through the OG books. Once I finished TTP and went into mock exam mode, I ran through practice problems in the OG's online question bank. Here I'll give a plug for GMAT Ninja. I found Charles Bibilos's youtube videos very helpful — not only for how to avoid tricks on verbal, but also for test-taking strategy in general.

My last piece of advice is to embrace gmatclub if you're on a tight budget, and to do so regardless during mock exams, because you'll find solutions posted to problems you get wrong. When I started out, gmatclub felt a little busy, and I wasn't in the mood to navigate forums. But I think if you commit to familiarizing yourself with everything that's offered (especially from Bunuel), you could accomplish a lot on a budget.

Anyway, for what it's worth, my two cents. Best of luck to everyone.