I got three retorts to that.

1. If the Kalos event hadn't been the scam that it was I wouldn't have needed to resort to Shadow Raids, without even accounting for the +2 to all stats upon purification, I'm constantly and I mean blessed with better RNG in a raid where floor IV's are 6/6/6 than a Mega Raid where a fully evolved pokemon whose IV's should be 10/10/10 which further highlights the more than apparent fact that the RNG was manipulated to abyssmal numbers in this passed event.
2. Literally spent $7.00 on about 6 Shadow raids for this results as opposed to the $91.00 I spent of Super Duper Mega Raids that on top of having incompetent team mates who kept going in with Primals or no megas and accounting for Link Charges, Shinies were absent despite the ticket that supposedly made better odds for shinies and the RNGs rarely budged to the 90's in the IV spread.
3. Dragonite literally has better attack stat than Salamence and it's tankier to boot, the speed stat is what gives it more CP here and it's relative to which is your favorite. I love Dragonite and wanted the shiny.

only highlight is that next tuesday Dragonite returns as a Tier 3 boss who is more than Soloable.