sydneyc

My golden rule :
1. If i play lots of e-sport games (csgo, fornite, ow) i'll get the 1080p 240hz monitor (144 is already very good if you don't have the cash for 240hz)
2. If i play mostly single player games, then i'll get a 1440p 144hz monitor
It really depends on what you'll use the monitor for tbh.

Save your money and get a 144hz. The difference between 144hz and 240hz is so marginal, your money is much better spend on internal components. 

For most people who sadly never had 1440p.
1440p is the new sweet sport for quite a while already... 1080p just doesn't make much sense for a good rig, it's a miss out on gaming experience.
Considering that we usually want a monitor to last many years (when we really invest in it), buying 1080p this late it's a terrible investment. 144hz is more than enough, even for fps players. 1080p is for 150$ monitors with budget rigs.

1080p is fine for most people, i dont see it as a waste, doesnt even matter if you dont have hardware to push 144hz 1440p.
 
~typing this at 1080p 144hz

As long as it's 1440p, 144hz is fine, only go for 240hz if you really have a lot of money to waste and you basically only play fps games. Just don't waste your money on a 1080p monitor.

Just know this, for monitors to reach 240hz, the manufacturers have to use tn or va panels instead of ips on 144hz monitors, tn/va panels are much worse than ips (some lower quality 144hz have va or tn panels but most have ips) also with the extra money you save you can upgrade your system or get a 1440p 144hz monitor instead of 1080p

Spend the money on the system. 144Hz is plenty.

144hz. Many gamers (professional) don't see much difference between 144hz and 240hz. They say the only upgrade u should definitely get is 60hz to 144hz. Here is a vid: