you'd have to pick jones in most of these what if fights. however there are so many what if fights for jones, who had a cozy HBO contract $5m per fight, even vs policeman frazier, eric & derek so long as WBA, WBC or IBF rated the opponent in their top 10-15. i see collins as a tarver type of fighter. obviosuly totally different fighting style. but what tarver did - beating old jones - , steve collins did in the UK, getting hold of faded stars benn and eubank and scoring high profile wins that set him up for a while. collins was formidable, maybe he could have made it competitive. i doubt he would have folded like merqui sosa did, vs jones. sosa was a strong, fairly slow pressure fighter (who never won a world title and always lost to world class fighters).
i'm a collins fan but i have to admit that a prime RJJ would probably beat him, but ya never know Collins could pull off a few surprises.
How is beating a 44-0 James Toney over rated? Roy Jones had the most natural talent of arguably any fighter in history. He would have easily disposed of Collins.
Collins hugely overrated (by himself as much as anyone, who can forget him lauding himself as "..not only the best super-middleweight on the planet, but the best pound for pound on the planet" after scraping past Eubank in their first match). Eubank dropped him heavily in their first match and hurt him in their second, Criag Cummings dropped him as did Kevin Watts. A peak Roy Jones annihilates him in around 6.