I now have Hawg Wired amps/speakers and love them but my buddy put just the hogtunes speakers in his bike and they sound good. Worth the bucks if you don't need way more than stock.
I swapped out the originals for Hog Tunes last year. No amplifier. I can set the volume 1 to 2 bars lower on the radio and still get the same loudness. The sound is also clearer on the highway.
With the stock speakers, when I got the volume loud enough to hear at 75 mph, the sound would distort.
Hogtunes have better clarity at higher volume than stock speakers. I used them on my last bagger. The nominal difference from stock didn't convince me I needed them on my current bike.
I heard a side-by-side comparison of Hogtunes and J&M speakers at a rally this summer. Both speakers were driven by the same amp with an A/B switch. The J&Ms were noticably better.