Like many people, I have read a lot of the negative reviews for Wizz Air and after flying with them a couple of times, I think that some of the reviews are unfair.
I have given them 4 stars as they deliver pretty much what you expect and their website makes it very clear about the baggage policy. It is a case of you pay your money, you make your choice. We did see people having problems with their bags, but they had brought huge cases and did not want to pay for them. The staff on the ground handling this I thought were excellent, very calm and just stating the airlines policy.
The planes are all pretty new, leg room is what you would expect, staff polite and helpful. Great routes, which open up some new destinations.
Read the website clearly and you can see what you are paying for and their will be no surprises. Also, they send a few emails reminding you about luggage size and costs.