As was said in a recent post, all you have to do is turn off the accompaniment to get a regular keyboard. Now what's the difference? Just cover up 'PSR' with a label marked 'Pro' and who's to know?. I'm with Accordianist. I can still play Dizzy Fingers (with a bit of practice) but it's also nice to have a bit of rhythm in the background. Same with Tico Tico (trying to sound like Ethel Smith for those who remember). And it's not only arrangers that are expensive. If I had to replace my clarinets I'm looking at US$2000 or more.
Bryan