I am going to have to respectfully disagree with you.
I hate to say it, but kits and purchased grapes will never be the same quality as a top tier commercial wine.
I agree that kits will never make the grade, but you can absolutely make a great wine that is as good as or better than a $20-$30 bottle of wine.
As a member of a wine club that has established a great working relationship with one of the largest distributors of grapes on the east coast, they regularly purchase premium grapes that can cost well over $100 per lug, but I've seen some spend upwards of $200 per lug to source the best available, this club purchases several tons of grapes each season and gets info direct from several vineyards, making the selection a very educated process.
I've enjoyed some of this wine on a few occasions, and I will tell you that most times it is far better than many commercial wine, not the $6 bottles either.
I'd put a few of my wines up against a few commercial wines, but I don't make wine to put into competitions, it is a passion, I enjoy the process, and I really like when friends and family enjoy our wine.
Those of us that are serious about wine making have purchased motorized crusher destemers, presses or bladder presses, enough testing devices or lab equipment to be able to make balanced wines, like any hobby, there are going to be expenses, it is all a matter of how much do you want to invest, be it time, money, or trying to help others.
I am very fortunate to be part of this wine club, which includes some of the best wine makers that I've had the pleasure of learning from, these guys are constantly pushing the envelope, using products, techniques, and equipment used in commercial wineries, they are always ready to learn and share, so to say that "purchased grapes will never be the same quality as a top tier commercial wine." is far from accurate, no disrespect intended.
I lived in Italy when I was younger, I helped my buddy on his fathers vineyard in Tuscany, harvesting grapes and helping to make the wine, I am fortunate to have been exposed to wine from an early age.
There is so much that goes into making a great wine, the most important is the grape quality, but that is just the start.
Sorry for the rant