I went with Alfa Romeo in Exhibition Season 3 and they're on my short list for 2020. I had by far the most fun with Alfa as a manufacturer and would summarise their strengths and weaknesses as:
Good
- Good on tyres
- Good on fuel
- Superb handling
- Good stopping power
- Gr.3 car is possibly the friendliest of the MR cars. The only time I struggled with it was the corkscrew at Laguna Seca.
Bad
- Top end speed is VERY lacking
- Depending on the multipliers the 4C's tend to be either utterly OP or mostly outclassed. There's not a lot in between.
The lack of straight line speed does make overtaking a challenge and you're always vulnerable on a straight, but you can really throw the 4C's around the corners, which is part of what makes them such good fun. Looking at the stage 1 schedule I'd probably skip Monza, but all the others are worth a go. Some of the tyre wear multipliers will work in Alfa's favour. When the multipliers are low and there's little to no choice on strategy, Alfa Romeo loses a lot of their advantages.
I should note that the Gr.4 car had a power boost and weight added in the recent BoP update and I've not tested it since then to see how that affects things.
I'm basically trying to decide between this, or an all rounder that will be competitive in most rounds. With Alfa Romeo you have to accept that some rounds you're not going to be in the hunt for the top positions, so either accept that and see what you can do or skip those rounds.