Being a long time fan of Gran Turismo (have played or owned every version )
controller setup ?
music in game or able to add playlist ?
Online ?
regular updates ?
selection of vehicles ?
amount of space on hard drive ?
I too have played every Gran Turismo, though I started to lose interest with 6 and ended up basically switching to Forza around then. GT5 is probably my all time favorite game.
Controls: This is probably my favorite part of switching to Forza. The physics engine feels slightly less 'smooth' when going from gripping to sliding across the road, but i actually think that's a bit more realistic. Yes, the steering is going to feel weird for 10 minutes. You'll figure it out. Assuming you're using a controller, i can't imagine you wont eventually learn to like the rumble triggers. Turn off the ABS, and you'll be able to essentially feel when the tires are going to lock up. Just brake until your finger vibrates then back off a few millimeters. Good fun. Protip: The clutch is fun and semi-hilarious. If you go into cockpit view you should be able to hear if you're actually doing it right (the game will let you grind gears with no consequence, but you cant hear the grinding from outside of cockpit view.) I honestly think there's not too much of an adjustment here. I don't really suggest the clutch for serious racing, but its fun to play with and essential for drifting.
Music: its terrible
Online: Online is a mixed bag. What do you want from the game? If you like racing super fast race cars.....the online might be pretty bad. If you like racing eclictic and kinda slow cars, the online is acceptable to good most days. If you like drifting, the online is great.
Regular Updates: Pretty good. Updates are still happening a year+ later.
Selection of vehicles: This is the other place i've been happy with the game relative to Gran Turismo. Don't get me wrong, i'm a JDM nerd and I do miss a lot of the Kei vehicles, the redundant skylines and RX-7's, Toyota...etc. I'm not going to sit here and say that the Forza car list is
universally better than the Gran Turismo one, but
overall, i do in fact think forza has a better list of cars, especially if you're comparing it to GT Sport...Anyway, relative to most
real GT games, Forza has more american cars and more european cars. They tend to be faster than what you'd classically see in Gran Turismo, but there are still plenty of slow cars. Forza also has a much better selection of old cars if that's your jam.
Space on hard drive: 100 GB give or take a few.