I really keep hearing and reading this from people who have made the switch. That for the RS having 90 more hp, it doesn't actually show when racing an st. I just want the AWD and the bigger gas tank (although mpg is much worse). But the extra 20k doesn't seem worth it for me, considering I can buy a 2017ish Audi a3 for that And have both. Then slap on a dtr6054 turbo and IC and have a mid 11 second car on pump gas stock fuel. Where the RS can barely break a high 12 second pass before you're leaning on the block.
They're definitely fun cars. My conclusion comes from when I got to DD a buddies RS for a week while I was fixing a few things and while he was on Vacation. St just "Feels" quicker to be honest. Of course I was 93 tuned at the time and he was stock tune/FBO.
Averaged like 22- 23mpg where the ST was doing 29-30.
For a Daily I'd still hands down pick the ST.
RS is still fun taking off for stoplights, but other than that, in the twisties and in the straights I'd still take my ST and the money I am able to put into it in mods.
It should be mentioned, the amount of maintenance on his car that he's had to do is more than the amount I've spent in mods year for year. Now his timing cover is leaking oil so that'll have to be done too.
Overall I feel like it's definitely worth the purchase for a first timer, but definitely not worth it coming from an ST.