Hi, if you're staying in major cities you may consider using tre:
This operator has only umts2100 (and sometimes 900) coverage, which is more limited than other operators, but it's much more cheaper. And it's nework is generally quite fast.
They sell 3gb/month for 5€. Sim is 3€ with 3€ traffic, so you need to top up at least additional 5€.
They have plan on sim for
internet key or on
microsim (ipad and similar)
I bought this sim some months ago and the first month was free (but now i don't find any trace for this offer) and you can deactivate this offer anytime at no charge.
Remember that if you're NOT on 3ITA coverage (you roam on TIM in gsm), internet is not included in the offer and it's really expensive.
So check
coverage here!
Otherwise you may go on tim/wind.
TIM has generally a really fast and performing network, and great coverage.
I may suggest
this offer, it's the cheapest and available for smartphone, tablet or key.
You should pay 5€ for sim with 5€ credit, so you need to top up at least more 10€, since you cannot use your offer with 0 credit.
Wind is actually, in my opinion, the slowest network, but everything depends on single cases. Coverage is quite good.
You may get
all inclusive, 7€/month for 1gb, 200 national min, 200 sms. Paradoxally the offer with only 1gb is 9€ month, so it's cheaper to activate all inclusive. Sim should be 5€