Boss WL-20L Wireless System

I wanted a wireless cable replacement that would work with both my regular passive pick up guitars as well as my EMG DG20 guitar. This was the solution.

For me, there is no perceptible delay. Manufacturers figures are 2.3ms and I have no reason to disagree with that. I've used them for playing live and recording with no adverse affects.

Pros:
Small and lightweight
Automatic pairing
Auto cut off so stop pops and bangs when plugging / unplugging
Great battery life.
Would fit majority of guitar jack sockets (probably all, but being cautious)
No noticeable tone change
Good value for money

Cons:
Ermmmmm....

Mine came in with an empty battery. After I charged it up the transmitter and receiver paired nicely, took just 10 seconds of LED blinking when connected and I have had no issues with it even right next to a WiFi router. Actives work (EMG 81x/85x, EMG Retro Active Hot 70), passives work (whatever it is on the Ibanez RG7321 as stock). I don't hear much of a difference - if at all - compared to a cable. Foolproof coloring and marked accordingly. Can be charged together and LED goes from green to orange when you have less than 2 hours of active usage left. ~12h for the transmitter, ~10h for the receiver.

I have purchased this thing primarily to get rid of too many cables hanging along my body when rehearsing, so as to achieve more freedom of movement and placement in the room. In this respect, I was surprised by the quality and consistency of the sound, even 4-5 meters away from the amp.
So much so, that i decided to try it out for recording as well, making A/B comparisons with a high-end bass cable. To my new surprise, it also proved reliable in a recording context, with only very little difference in comparison with a fully shieldied, gold-plated , high-end cable.
It has reasonable autonomy (approx. 2 hours) and is easily recharged with a common phone charger.