I bought my CYO 60 a couple of years ago from Dot Bike. At the time they were cheapest when postage was added. Annoyingly I was in The Hague a couple of weeks later and saw one significantly cheaper in a shop window.
I've been very pleased with it, but it is dim near to the bike. I think though that if you haven't seen the pothole, stone, whatever by the time it's in the darker bit you'll hit it anyway!
The sensor is a waste of time. If the model with just a switch is cheaper I'd advise getting that instead.
I've never fitted the Shimano regulator. It's really to protect rear lights if a front bulb blows and my thoughts are that with a top quality LED front light and integral wiring to the back one that's not a problem. If the front LED went open circuit then the main casualty would be the LED at the back which can be replaced for a couple of pounds, and possibly the standlight capacitor at the back which is another couple of pounds worth.