Ubiquinol is a waste of money. It's unstable and ubiquinone and -ol are freely converted intracellularly. Anyone pushing -ol is unfamiliar with CA-cycle. Yes, it's more bioavailable, but that's without meaning in terms of cellular-respiration. In terms of its pseudo-stimulant properties as the result of its impact on cell-met, sympathetic NS activity (preganglionic neurons) and mitochondrial deficit--try to sleep after taking 1,200mg or more of CoQ10 after 3pm--you won't sleep.
I've been hitting the Concept 2 erg everyday for a couple of years. My 2K time is 20 seconds better, on average, after ingesting 2g of CoQ10 vs. training without CoQ10.
Concept 2 rower? Been using that more and more in CrossFit. Still sore from 500m sprints last Wed... Might look into the CoQ10 for a burst....