This raises another point -- each vendor makes multiple lines of kits of differing quality. For instance, WineXpert has 3 main lines:
Classic -- lowest juice/concentrate ratio, lowest quality
Reserve -- middle juice/concentrate ratio, medium quality
Private Reserve -- highest juice/concentrate ratio, highest quality
The word "quality" means with respect to the other lines of WineXpert kits. Most people who've made WineXpert like the brand, and all their lines make good wine. However, in general, the higher priced the kit, the higher the juice/concentrate ratio, the better the final product, and the longer it needs to age.
In addition, WineXpert makes:
Island Mist -- low alcohol wine with a fruit F-Pack, a "fun wine"
LEyy -- each year limited edition kits of are sold. I believe these are equivalent to the Private Reserve or maybe a bit better.
R J Spagnols (abbreviated RJS on this forum) is of comparable quality and also has numerous product lines.
I've had success with both brands using all levels of kits.
IMO, make a few lower end kits first, then go with higher quality. This way you have wine to drink while the better stuff is aging.