I would advise listening to some of the most best and most expensive SET amps you can find. Preferably listen on a very good single driver loudspeaker system of high efficiency. This will give you a "benchmark" of what a good SET can do.
One of the worst things to do, is to audition the "affordable" SET amps with the attitude stated above like "at least I won't be out alot of money if I don't like it". One of the most important parts of a typical SET amp is the output transformers, and excellent output transformers cost a lot of money. If the SET amp you audition has cheap output transformers(like the "affordable" ones usually do), then you'll experience the top-end rolloff and bass bloat that accompanies cheap output transformers. Then you'll think that SET has poor sound and go back to normal stuff. But, in reality, SET amps can be awesomely good if they are built right and have the right speakers mated with them. This usually means expensive, because output transformers for SET amps that are very high quality are generally very expensive items and this adds considerably to the price of the amp(and also to the better sound).
Basically, SET amps are not measured by "dollars per watt", but by sound quality. You need to have a good one to realize what they are capable of. The really good ones have excellent frequency extension, and can have some of the most coherent lifelike sound available at any price.
Make sure the speakers used have a relatively stable 8 ohm, or higher, impedance curve without any deep dips, and have above 95db efficiency, and you should be ok.
One of the worst things to do, is to audition the "affordable" SET amps with the attitude stated above like "at least I won't be out alot of money if I don't like it". One of the most important parts of a typical SET amp is the output transformers, and excellent output transformers cost a lot of money. If the SET amp you audition has cheap output transformers(like the "affordable" ones usually do), then you'll experience the top-end rolloff and bass bloat that accompanies cheap output transformers. Then you'll think that SET has poor sound and go back to normal stuff. But, in reality, SET amps can be awesomely good if they are built right and have the right speakers mated with them. This usually means expensive, because output transformers for SET amps that are very high quality are generally very expensive items and this adds considerably to the price of the amp(and also to the better sound).
Basically, SET amps are not measured by "dollars per watt", but by sound quality. You need to have a good one to realize what they are capable of. The really good ones have excellent frequency extension, and can have some of the most coherent lifelike sound available at any price.
Make sure the speakers used have a relatively stable 8 ohm, or higher, impedance curve without any deep dips, and have above 95db efficiency, and you should be ok.