Sure. You have marginally higher chance of getting higher quality items. However, the increase in difficulty means it'll almost certainly take longer, so it's generally not recommended. Usually people aim for 23 or 24 if they are going above 20, depending on affinity.

Glyph drop rates are the same, materials drop rates are not. For CvC points, 21 is obviously better. You can expect an average of 16 epic and 11.2 legendary materials per run for level 20, compared to 27/11.9 for 21.

Aside from the rates being slightly better overall, it may be worth it simply for being closer to the desired 2:1 ratio since that's the ratio of forge materials used in crafting. If you can do 21 on auto in a reasonable time, go for it. If not, doing 20 is fine too, but less efficient as far as the forge is concerned. For glyphs, it makes no difference.

It takes me about 8 mins to do 21 and 3 mins for 20.  I am not in a rush so will keep doing 21.  

That's somewhat misleading, though. 20 uses 16 energy, vs 21 using 18 energy. So, while you may get better rewards on 21, you won't get *more* rewards. The comparatively higher rewards on 21 don't outweigh the fact that you're using 12.5% more energy to get them.

That's why most people focus on 23/24. From what I remember, 23 is the breakeven, although it's possible that 22 may also be enough.

my guy, I think you're a bit mixed up 😂

they're talking about Faction Wars.

... Yes, I'm definitely thinking FK, not FW. Apologies. I'll see myself out.

happens to all of us fella. good luck in CvC if you're pushing. 👌

😆 

I dont see any big differences in glyph drops. Fw21 can drop 4 star glyps too and FW21 do thats many times. I can complete all 21 relative fast, years ago, but i do just in CVC.