Didn't realize the C200 and 300 were not pneumatically balanced. I guess I should have done my homework a little better. Sub Gear users out there, what are your thoughts on SG's mid range regulators, the Bonnaire and Aruba?
My understanding is that unbalanced second stages are more popular in Europe than in the US as an upscale second stage.
In a way I agree with that, provided the unbalanced second stage is well designed and not just regarded, manufactured and marketed as a cheap entry level second stage with more or less a designed obsolescence approach where the intent to sell a new diver a beginning reg, then later a more advance model.
When I bought my first new reg in 1985 it was a Scubapro Mk 3 High Performance (what people call the 108 second stage). It was very well made with over all quality and execution of the design on par with the unbalanced "Adjustable" and balanced version of that second stage, the "Balanced Adjustable" from the same time period. More importantly, when placed on a balanced first stage it would deliver cracking efforts that were as low as those on the Adjustable and Balance Adjustable, and it delivered the same very smooth airflow. In short, it and the Adjustable were very high quality unbalanced second stages.
That more or less changed when the R190 came along and over time it appears that the less expensive unbalanced second stages also became victims of much wider quality control processes. For example, I've noticed over the years that some R190s can be made to breathe very well with inhalation efforts on the order of 1.0-1.1" of water (about as low as they can go anyway due to CGF issues), while others struggle to meet a 1.4" of water specification. On those regs you end up having to swap and perhaps other parts to get the performance to the same level, suggesting they have much wider QA specs and issues with tolerances stacking in the wrong direction. Same story with the R380, R390, R295, etc, just aggravated by the smaller diaphragm that powers them. Another issue was the plugging of one port in the aspirator changes in the flow vanes, etc, apparently to meet CE standards which have unfortunately become a necessary evil in the regulator, and haver over time degraded the performance of many models to meet truly useless CE free flow standards.
In any case, it was refreshing to see the C200 and C300 designs as they do seem to be an effort to field an unbalanced second stage with first rate quality control and first rate performance. The models I saw at Beneath the Sea impressed, me enough to order one but when it finally arrived several months later, I was and remain less than fully impressed with it's particular performance. I have not given up on it yet (and it has proven to be very reliable) however as the engineering on it appears to be very sound and it's avoided the pitfalls the X650 had with a similar lever design and a similar poppet guide system. Learning obviously occurred and was carried forward into the C200 and C300.