"serious" is a subjective opinion when it comes to blisters. What one may think is a serious blister problem may not be so bad if it's assessed by someone who really understands what's going on. How many blisters are we talking about; localized area or all over the bottom? How big are most of them; dime, quarter sized, or bigger?
No, too many variables involved to associate with any one model or brand.
Blistering can happen with any brand
Impossible to say without knowing the extent of its condition. Only then can one determine what it will take to remedy. If it's the entire bottom, I can tell you that to do it right, it will be costly. It's labour intensive and the right materials are pricey. Then there is no guaranty new blisters won't show up in the future after the job is done as one can only repair those that are currently visible.
I assume you'd get a survey done regardless but when it comes to the blisters, have a qualified fiberglass technician assess the severity and give you an idea of what it'll take to remove them. Remember, unless they are so bad that they actually affect performance, they are more of a cosmetic concern, not a structural one. Having said that, in the eyes of most buyers who don't understand them, it's a turnoff, and because purchasers determine an item's worth by what they're willing to pay, it may pose a problem for resale later.