I'm using Behr paint, so I'd say that not low quality.
Actually, Behr is a low quality paint. It's the "affordable" brand that Home Depot carries and promotes as their easy-to-use primer+paint combination. I've found it difficult to get a nice clean layer on whenever I use this paint. I would avoid using Behr and go for something a little higher quality.
Glidden and Sherwin Williams, are the two brands I usually use. Though I think Glidden is a Canadian paint, but I know SW is American and all over the USA.
Be sure to apply your paint in a nice thick coat, but not lumpy. You still want the amount of paint to evenly coat the surface, but have enough on there so that it's not "thin". I tend to glob it on, then use my roller to smooth it out. Using a fine roller is good, but you don't need to apply too much pressure to get coverage.
Also, start your sanding passes on your layers early. I usually start sanding in my primer pass, then every pass after that. Apply your coat, let dry for a few hours or until the paint is "tacky", then lightly sand using a high-grit sandpaper, then gradually getting higher towards your last pass. You just want to sand the paint surface till it's smooth in each pass. For me, I put 2 - 3 passes of primer, then 3-5 passes of paint, sanding in each pass.
It's worked out great for me, and I have no complaints of the end results (check out the first page of my Canucks cocktail in my sig, the paint job was done with this method and it looks awesome).