There have been other threads on this topic. The PSR2000 is way better. I owned both. The PSR2000 has a lot of functions that aren't explained well in the manual, so it might appear that the keyboard is buggy. Actually, the keyboard has very few bugs, and none that affect my performing.
Besides the PSR2000's internal styles, which are slightly better than the PSR740, I can store about 25 favorite styles in flash memory. Then I can access styles off of a floppy in about 2 seconds. On the PSR740 it takes about 12 seconds. As you know, when you are performing, time is critical.

In addition, the PSR2000 has some good additional voices. The Grand Piano sounds a little bit better too.

I guess that the most convincing thing for me is that my audiences at nursing and retirement homes have mentioned hearing a difference in the music and are extremely impressed.

The PSR740 is a great keyboard. Many on this forum made and perhaps still make a living with the PSR740. It also has some bugs too by the way - and limitations that bug the professional user.

The PSR2000 is worth the extra money - if you have it.

When I got my PSR2000 there were a couple of features that I thought were broken, but I actually didn't understand how these features worked.

Larry