Yes Rekordbox 5 is really a big improvement and I really liked it as well, the interface is much better, more features and much less consumption of CPU and computer resources. In my opinion this was a good decision to review what Pioneer made in the last 2 years and redesign the software and launch version 5. I am sure this costed a lot of money and normally is hard decision but important to gain more users.
What is need now is to do a fine tunning in terms of stability with the aim to gain confidence of DJ's to use it in their live performance (Performance Mode).
If Pioneer be able to fix some issues in a short term I am sure this will leverage the usage of software.
I have some open inquires that are under investigation I hope they find the issue and fix it them I will be able to use my DDJ-RZX in live performance without fear.
I used Serato DJ during 3 years and I faced several problems, this week I also looked in Denon forum to see the perception of the users about their products and there are people also complaining so at the end there is no perfect software or hardware, Pioneer has excelent products so we just need more stability in terms of usage.
Keep Going Pioneer !
Sergio