Drone will be in a different range for different exhausts. I have drone from 2-2.5k outside of that it is stock sounding, no sound at all. As OP said, a muffler delete will tend to drone from 1k-2.7k. Really depends. As time passes, either you'll get used to it, or you'll hate it and put the muffler back on.
2007 E90 328i - Titanium Metallic l 19" VMR V710 l H&R Trak+ Spacers l Mtech Rear Lip Spoiler l Eibach Sportline l AA N52 Signature Exhaust l OEM Blacklines l MTEC V3 AE l 6000K HID l Nokya 7000K Fogs l MTEC License Plate LED l Interior LED l 15% Tint l BlackVue DR380G-HD + PMP