I've checked out pilots with FAA PPLs here, they range from very good to well below average.
But one pattern emerges and that is the ones who have gone for the "guaranteed PPL in x hours/weeks/dollars". These seem to suffer from a common problem which is lack of confidence and ability to deal with anything unexpected, IMHO due to the lack of time to consolidate, or just sit back and have a rest and let it all sink in. It's a shame, because some of them have been so nervous they have admitted to being scared stiff of flying solo; their confidence has had to be built up from scratch, along with many of their basic skills. One had been issued a JAR PPL but only had 1.2 hours of IF time!
In general it's true that you get what you pay for, and sadly these el-cheapo outfits give pilots unrealistic expectations, and many potentially good pilots are ruined on the way.