I have one of these x62's in the i5 version, bought it prebuilt. The screen was quickly updated with the LED backlight mod as well. Honestly, coming from an x220 and x230, this thing flies. Highly recommend one. I also have an x61s that is nice, but the resolution and speed is not modern enough for me.
Performance of the x62 is on par for sure. Mainly because the hardware is swappable between them. The relative gain in resolution for the size/weight between a non-fdh modded x2*0 and the x62 is the main takeaway. I also gained miniDP and usb3 which the x220 does not have.
Regarding the LED? Monty, who makes the kit, is an awesome dude and great resource. I emailed with him regarding installation and he quickly responded. Installation should not be for someone without a history of taking these machines apart. You must have the willingness to dig a little deeper than a RAM install, as you are disassembling the screen bezel and making permanent cuts into the plastic and on an expensive x62 prebuilt, this took serious consideration.
The cuts are easy, and the disassembly is easy. no soldering or real issues I can remember, other than having to do it twice because of dust. Do the whole thing in a clean area without a rug, vacuum everything around first.
I highly recommend the kit. Brightness is on par with brand new machines. Just shield your eyes from the LED kit turning out before it's in the screen. SOO BRIGHT
