To provide the reader (and the potential user) with a bigger picture, we selected a RCM reaction of (-)-L-isopulegol (a monoterpenic alcohol that is widely employed in the flavour and perfume industry) derivative 32 (Scheme 6C). This RCM reaction-leading to formation of a tetrasubstituted C-C double bond-is known to be problematic for a second-generation catalyst used in 1 mol% loading under standard conditions (conversion ~30%). In our tests we conducted RCM of 32 under previously reported conditions (benzene-d 6 , 60 °C, 2 h, 0.25 mol% of catalyst), comparing Ru16 and Ru17 with selected known "small-NHC" catalysts. We found that (with the only example of macrocyclic-NHC derived Ru14b) new complex, Ru16 was giving the highest conversion (89%) of diene 29 into bicyclic product 30 after 2 h. Prolongation of the reaction time to 20 h increased conversion to 91% (Scheme 6C). Interestingly, the fluorinated analogue Ru7 led to lower conversion (78%) in benzene, probably due to imperfect solubility in this solvent (cf. discussion about reaction 24→25; Scheme 5), while in perfluorobenzene at the same temperature the conversion was improved to 85%. Interestingly, the specialised SITol catalysts that are commercially available (Ru3 and Ru4) gave 76 and 79% conversion in this reaction, while their close cousin Ru11 offered only 61% of conversion. The SIXyl version of the latter, Ru12, led to 64% of conversion to product 30 (66% after 20 h).