Vortex Sound Research

Hi guys! I have 1000$-1500$ budget to grab a new synth. I know one is a poly and the other one a mono synth. What I'm looking for is a synth for filthy and fat basses, leads as well as for creating fx. Do you guys think the Grandmother or the Peak is better for me? If the Moog is a lot better than the Peak for creating those types of sounds i might consider buying that one instead of the Peak and it's ability to produce polyphonic sounds. PS: If you guys think there's a better synth for me in that price range definitely let me know! Thank you!