Arion is an old school pedal maker from back in the day. In the 80s when there were just a few companies making pedals Arion was the budget line. The Arion SDI-1 is a cheaper version of the Boss DS-1. From left to right the knobs on the SDI-1 are Level, Tone and Distortion as opposed to on the DS-1 where the knobs are Tone, Level and Distortion. Since this is a stereo distortion pedal there is two outputs with the one input jack.
Like any good foot pedal it has a large foot switch on the face of the pedal. On the Arion it is made out of plastic so I do not think it would hold up to much abuse. With only 3 knobs of adjustment the tone shaping is easy. On the top there is a switch for direct and soft. This further changes the tone you can get from the pedal because in the direct mode it makes one of the outputs an effects bypass. So with the dual outputs you can run one amp dirty and the other amp clean at the same time. This is a feature the DS-1 does not have.
The distortion sound from this pedal is not very good. The distortion sounds very thin and brittle. The controls do what they say they do. The level knob increases the output while the distortion knob increases the saturation. The tone knob seems to increase the mids and high end. Turning up the tone knob on the pedal can make the sound coming out from it almost painful. The gain does not really sound natural at all.
If you are a beginner and are looking to build a pedal board of sorts Arion pedals may be a good choice for you. You could build a pedal board with all the different pedals you need to have then over time upgrade the pedals you use the most. This pedal is good for its role. If you are a beginner and your amp isnt that great or its an old cheap amp and you want some more gain this pedal could be what you are looking for.