Lifestyle will very much depend on you. (regardless of the company)
Coming as a single Captain, it's fine.
Coming as a married Captain with kids, SIA package Ok, all the other companies you get by, can have a comfortable lifestyle, but there will be no money left at the end of the month, consider seriously if you want to become an expat and not be able to save.
If you are coming in as a FO and single fine, but also not too much left at the end of the month.
If you coming in as a FO and bringing a family, I would strongly advise against coming. Rent (assuming you want a comfortable house for the family), perhaps a car, kids schools, etc - it will be very hard to get by. Or leave the family in Europe until you get the upgrade. It may not sound nice, but I am being realistic.
Just my 2 cents.