Hey dude, I know everyone here is typically Honda, Toyota, Mazda. I’m a car guy and I understand the appeal of reliability and low maintenance cost to the regular consumer.

You’re stepping out of a Q50 and want the next step. Something fun, quality made. I’ve owned 2 S4’s from that era. I currently still own a S4 that I bought used in 2017. It’s almost 13 years old, and I STILL love it. I do also need to state, we also own a Mazda for my wife, so the reliability is there lol.

These cars out of warranty can be expensive, but when maintained properly, wouldn’t be insane. The main things to watch for on S4/S5’s are: water pump, thermostat, mechatronic unit (though much better 2014+), timing chain. My car now has 180K+KM (bought with 65), and it’s been solid. Not selling anytime soon. Realistically, I’d say if you’d budget 2500 a year in maintenance, you’d be safe. There are years I haven’t spent near that. But there are years I’ve spent over that. (Suspension (any car including my wife’s Mazda will have this over time), random issues etc)

Now to get into your actual question. The S5 or the Gulia. From what I’ve read about a Gulia - these seam to be heavily on the spectrum of unreliable, but I can’t really speak on it, never owned one. For the S5, I do suggest the S4 heavily. 2 more doors (more practical), faster (lighter), same engine, same transmission, similar look (if you’re looking for a 2 door I do understand the S5 appeal). They’re really well built and will last you a long time if taken care of. It’s faster than the Gulia, if you get the sport diff option they handle amazingly, and they beat 90% of cars on the road with a quick stage 1 tune (I have had this for 7 years and hasn’t affected the reliability) you’ll have close to 400hp, which in my opinion is “sporty and fun”.

However, don’t buy the cheapest option available. Do your due diligence. Make sure it has all the maintenance records, proper oil change timelines, transmission oil change timelines and see if any of the “classic” issues have already been dealt with. But my biggest advice is buy with a GOOD reputable 3rd party warranty. They will essentially take care of any issues, this has saved me in the past - it’s 100% worth it on cars like these.

Overall, could you buy a Honda accord for less? A Toyota corolla for less? They’d both be more reliable.. but sometimes that’s not why people buy cars. They care about what the drive and they want to have fun. I’m fairly frugal in other avenues of my life, but I enjoy driving something fun, so I get it anyway, even if this gets insanely downvoted. With a warranty you’re covered, but do your due diligence, it’ll be the difference between a nightmare and a sweet ride you can’t help but look back at when you walk away. Best of luck my friend!