I have 7 pedals on my pedal train classic Jr board and there is a single pedal upon which MY tone hinges, my Diamond CPR1 Compressor is the most important ingredient in MY tone. I do not like high gain as I've always considered it a barrier to hearing how I am sounding. I prefer a low to medium gain sound which the CPR1 just gives that tiny push into exactly where I want my sound to be. The CPR1 is amazingly transparent and you just never did hear a more silent pedal, it's one of those you notice when it's not switched on as something sounds missing. I would never be without my cpr1 and it's the most pro sounding pedal on my board, it's the one that holds my tone together for sure. Which pedal is crucial to your sound and how would its absence decimate your tone ?