I think the best is to wait a bit if you can. There will be a few comparisons sooner or later, and the price of the TS-PC will drop.
Now, at 550€, for me it's way too expensive, it's more expensive than the CSL Elite + P1 wheel (more universal + xbox one compatibility, 320 + 150 + 32€ shipping to France, probably the same to Italy => 502€) and almost as expensive as the CSL + Formula wheel (320 + 230 + 32 = 582).
Honestly, without more information on the FFB and assuming they are very close, I don't even understand how anybody can advise to buy the TS-PC until its price drops, IMHO the quality of the wheel is just day and night between both brands (the price too, but the CSL base is obviously cheaper at the moment).
And if you plan to get the CSL Elite pedals (excellent choice, the loadcell is by far the most noticable improvement, it changes everything), the shipping cost will increase of only 15€ to add the base + 1 wheel. If you choose the P1 wheel, you can even save 30€ (10€ discount + 20+€ if you sell Assetto Corsa XB1) more with the Assetto Corsa bundle.
And as said in the previous post, the resale value of the CSL base will be much higher if you change later for a future better base.
All in all, the final question has to be "do you want to be in the Thrustmaster or the Fanatec family for the future", because you'll perhaps add more accessories (shifter, handbrake) and/or change just the base and keep your wheels. Changing from a G27 is one thing, changing from a brand to another when you've 2 or 3 expensive wheels is another.
Both bases are very good and I've seen only positive feedbacks about their FFB, so the slight differences of quality there could be regarding the FFB may not be alone what decides you for one brand.
If you prefer Fanatec, just buy the CSL.
If you prefer Thrustmaster, if you're not in a hurry, wait 2-3 months for a price drop, if not, just buy the TS-PC.
If you have not a clear preference, just wait a few comparisons to decide.
