Boss LS-2

The LS-2 is worth its weight in - well, not gold, but close. A while ago, I've bought a second unit to gain more flexibility in experimenting with groups and chains of many various pedals, looking for specific sounds. I wanted to be able to switch between groups at the push of a button, and easily compensate for volume differences between the groups. The LS-2 does all that.
Switching: One of the best things is that you can switch between the A/B effect loops, A/B/bypass, A+B mix/bypass, and Output select (e.g. for switching between amps). So easy to switch between solo and rhythm sounds that consist of two or more pedals. The footswitch itself is as sturdy as any Boss pedal, and the one on the LS-2 is silent and 100% efficient. Bypass is true, didn't notice any signal loss.
Power: Use a Boss PSA unit (or another stable & isolated 9V power supply) though, or you'll get an amount of free noise. From the LS-2 you can forward your stable 9V to a couple other pedals; so far I haven't heard any ground loops when powering up some (A/B) looped pedals from the LS-2.
Definitely worth it, highly recommendable.

I have a pedalboard with 10 pedals and sound and volume loss was always bugging me. I bought a true bypass looper from another manufacturer, and out all pedals into a single loop, but volume difference between bypassed and non-bypassed signal was too big.
Boss LS-2 solves this problem because it has a volume knob where you can fine-tune the volume level of the loop. The volume of both loops separately, to be exact, although I don't use it that way. So, to put it shortly, all my pedals are in a single loop of LS-2, which means I can turn multiple pedals with a single press on LS-2.
Bypass buffer is standard for Boss - there is a minor high frequency loss, but that is nothing compared to sound loss that happens when you connect 10 pedals in series.
I love it and it is a permanent addition to my pedalboard.

I think everyone looking at this product knows what it can do - this is rather specific little tool . However It has so many possibilities that It has completely changed how I think about my setup.
This is the perfect tool for hardware nerds.
Use mine for multiple purposes but my most used method would be mixing my dry bass with overdrive pedal board.
Also perfect for running different instrument through the same effect loop.
Being a boss pedal the hardware is sturdy and built to last and there seems to be endless possibilities to this product, really happy and would buy again.

Can't really find anything to complain about.

I have had a fair few of these pedals over the years depending on how my pedal board was configured. You can do so much with it: select from up to 3 different guitars, select various outputs, select different loops of pedals and mix dry signals with wet/effected signal ratios. I still have one for plugging two guitars into one amplifier (and having separate control over both their outputs) for when I'm teaching, but I have found this pedal to be noisy -even when the volumes are set for unity. For this reason I wouldn't use it as just a boost pedal because with distortion the noise soon becomes an audible hiss, and for this purpose there are a growing number of better, alternative pedals. However, all in all for almost any switching needs, this is a great pedal at a very reasonable price.