It kind of depends on what's most important to you and how much you want to spend. Would you prefer 27" or 32"? Most of the high refresh rate options at 32" are VA panels, there are some IPS options but they are usually significantly more expensive.
To take an example, Asus also do 32" monitors like the below:
The ASUS XG32VQ is a 32" 1440p 144Hz FreeSync curved gaming monitor boasting the premium ROG branding. Is it better than the alternatives?
www.displayninja.com
When compared to the Asus Tuf you mentioned, that 32" will have better contrast, so deeper blacks making it better for watching movies in the dark. However it will have a slower overall response time than the Asus Tuf, so your more likely to see a slight ghosting effect in fast moving scenes at 170hz. It also wont look quite as good if you are viewing from an angle, for pc gaming where your right in front of it though that's probably not too much of an issue. Whether it's significant enough to bother you I don't know as I don't own one and have never used one. It's a similar situation with the Dell, it's a very nice monitor but similar weaknesses in the reviews about the viewing angles not being amazing, slightly disappointing at high refresh rates.
These are the rtings reviews for the Asus and the Dell:
https://www.rtings.com/monitor/reviews/asus/tuf-gaming-vg27aql1a
The Dell S3220DGF is an impressive 1440p gaming monitor. It has a curved design and it doesn't take up much room, even with the support stand attached. Gaming fe...
www.rtings.com
In both actually they recommended an alternative if response time was the priority. Most people who buy these monitors are very happy with them, none of them are bad displays by any stretch but they have their pro's and con's. For some playing on a 27" just isn't immersive so they want 32". I can only tell you what I would do, I was in the market recently for a new monitor. I looked at 27", 32", 34" ultrawide and both IPS and VA panels. I ended up going for a 27" 165hz IPS, so if it were me I would lean towards the Asus Tuf or something similar.