Class D Amps, and enhanced signal processing has really improved A LOT this decade. The lower budget brands produce sound quality better than the middle level stuff from YEARS ago did.
If the typical Yamaha or Peavey, JBL, Carvin, EV stuff etc. was adequate for mobile work 20 years ago, and people thought sound was great then. Then, the typical audience would probably think the sound from Newer budget stuff like Harbinger is good as well.
Today, the cost of gear that is adequate or good is cheaper for mobile work. In the end, Tech has become better, equipment has become cheaper, and the means of getting it is easier (Internet, Credit, 0% financing etc. )
My opinion is it doesn't sound as good as old gear. The fact everyone listens to MP3 and not vinyl or CD now hides a lot of bad sound. People really don't know good sound anymore. That being said I have never compared vinyl on my old Cerwins to the Yorkies but I have compared MP3 and the Cerwins sound much better