Large pen tablets have an active area diagonal size of about 15".
Even if a tablet has "large" in its name, it doesn't mean it us truly a large tablet. A perfect example is the Huion Inspiroy 2 Large which is more of a medium sized tablet. Same with the XP-Pen Deco L/LW.
Using a large tablet is very different from using a medium size tablet. There are many things you have to adjust to. More here: Using large pen tablets
Intuos Pro Large (PTH-860) - my notes on this tablet
XP-Pen Deco Pro XLW (MT1592B) - my notes of this tablet
Huion Giano (G930L) - my notes on this tablet
In terms of drawing performance the best of the three is the Intuos Pro Large (PTH-860).
Second is the XP-Pen Deco Pro XLW GEN2 (MT1592B). The things to note about this tablet is the excellent design and vastly improved pressure handling coming from its X3 Pro pen.
Third, the Huion Giano overall is very good. It's a very close third to the XP Pen Deco Pro XLW GEN2 because the PW517 pen does not handle pressure (smaller pressure range for example) as well as the X3 Pro pen.
Model number
PTH-860
MT1592B
GT930L
Release year
2017
2023
2022
Pen
Pro Pen 2
(KP-504E)
X3 Pro
PW517
Retail Price
$500
$200
$200
Common On-Sale Price
$400
$170
$170
Used on eBay
$150 to $250
Intuos Pro Large - https://estore.wacom.com/en-us/tablets.html#wacom-intuos-pro-link-anchor
Deco Pro XLW GEN2 - https://www.xp-pen.com/product/deco-pro-gen-2-series.html
Intuos Pro Large
12.1" x 8.4" 311mm x 216mm
14.7"
1.44
Deco Pro XLW GEN2
15" x 9" 381mm x 228.6mm
17.6"
5:3 (1.67)
Giano G930L
13.6 x 8.5 345.4mm x 215.9mm
16"
16:10 (1.60)
None of these tablets have an exact 16:9 (1.78) aspect ratio.
So, you should ensure you match aspect ratios with your monitor before you start drawing.
The Wacom Pro Pen 2 is the clear winner, but the XP-Pen X3 Pro is good. The Huion PW517 is just OK.
In my experience I see that the PW517 units vary quite a bit in their maximum pressure. The average of my tests is about 200gf.
Wacom Pro Pen 2
<1gf
~800gf
Huion PW517
3gf
~200gf
X3 Pro
2gf
~400gf
Tablet age - don't let the fact that the Intuos Pro Large was released in 2017 dissuade you. It's still better than the most recent tablets put out by the competition
Pen replacement cost - Keep in mind the Pro Pen 2 is very expensive ay $80. It's a significant cost if you need to replace it. The PW517 is $50 and the X3 Pro is $40.
Nib wear - the Intuos Pro comes with a surface that (at least initially) has a lot of texture and can wear down nibs fast.
Wireless - All three support Bluetooth wireless connectivity
Touch - only the Intuos Pro supports touch.
Auxiliary inputs
Intuos Pro Large - 8 total buttons
Deco Pro XLW GEN2 - no buttons
Giano G930L - 6 buttons
Remotes
Intuos Pro Large - no remote
Deco Pro XLW GEN2 - comes with remote
Giano G930L - no remote
Intuos Pro Large - Low (good)
Deco Pro XLW GEN2 - some wobble at slow speeds OK
Giano G930L - Low (good)