It's exceptionally rare to find an RDA that does both single and dual coil well. I'd suggest looking at ones which are dedicated to single or dual set ups. Also, the Nitrous RDA is an exceptional atomizer. So your options for other RDAs that can rival its performance is short.
Single coil: (these are best used on a squonk mod in my experience)
The Reload S RDA is still probably my favorite single coil for DL vaping. Reload Vapor has both black and SS versions for $60 + shipping right now. SXK made a quality clone of them too, but they're both currently listed as discontinued. Although I might have a brand new black SXK clone stashed away if you don't feel like paying $60+
The QP Nio (Remastered) is also a great single coil RDA. And it's only $35 + shipping if you buy it direct from QP, which is a great deal for everything you get
The Skyfall RDA is another great single coil, though it's designed more for RDL than DL.
Dual coil: (I look for taste over clouds in all my atomizers, including dual coils)
An RDA for Vaping by Coilturd is my absolute favorite dual coil RDA. Plus you can pick up some Bule Bolu liquid when you buy it directly from Coilturd
The Pulse v2 RDA is still one of the best RDAs I've ever used, despite is being a cheap/mass produced atomizer.