I had set the Ryobi up with a 16 inch bar, but put the 18 on it for the reach.
I think you were the one who started the whole Ryobi thing on this forum?
I got some Charlton Premium 12" from Baileys when they were less than $10 with chain. Only have about 10 3/8" sticking out past the 'dogs', but if I'm cutting over 10" I should grab a bigger saw. You might have a point on the 'reach', I suppose I could try putting a full comp chain on the factory 18" bar and see if the extra length slows it down any.