I have used the Strymon Timeline delay since 2014 and I really cannot fault it, the quality is as expected from everything Strymon produce, awesome and the sounds it can produce are simply amazing.
I primarily use it for guitar and find the looping feature very useful for creating guitar parts and playing off them when I am playing alone. The only wish I would have is to be able to loop record for a little longer although that said, the actual looping time is no real impediment to its usefulness.
The quality and clarity of the modulated echoes are stellar and give quite a few high end rack units costing a lot more a great run for the money it costs, no doubt this is why its commonly found in so many guitarists pedalboards and racks, I also use it for recording as a send effect and I get great results with vocals as well as keys/guitars.
One of my favorite effects this unit provides (as well as echo) is the almost synth like crystalline tracking of the pitch shifted echoes, this produces in my opinion one of the best examples of this effect which I believe originated on the high end Eventide Harmonizer rack effect units and is often used by the likes of The Edge from U2
If top quality echo and ambience is your thing, you will not be disappointed with this unit, it has a wealth of amazing features and can be expanded upon by adding one of the 3rd party add on pedals on the market which can greatly expand on the already brilliant looping features.
An excellent delay effect and definitely one to have in your arsenal if you need something to sweeten your sound up and produce great ambient sounds!
10/10!