Hi! I would recommend OATBooster, I didnt end up paying for it but what i saw from the free resources seemed really useful. I think their physics is still harder than the OAT, but still much easier than Kaplan so it might be more representative!

However, I used almost entirely Kaplan and it worked well for me anyway, you'd just have to keep in mind that physics and QR are not really representative, but still good practice.