I'm upgrading my final 5.1 server to new hardware and to netware 6.5 Hooray!!!

I've got 3 servers total, 2 6.5 servers with SP5 installed, ds version
10552.79. The new server has SP6 ready go go, dsversion 10553.73. The old
5.1 server has edirectory installed to 10551.29. 2 Questions.

1. Will the DS version difference between SP5 and SP6 be an issue when I

2. If so, would it be better to wipe the server and go back to SP5 and set
this up, or easier to upgrade the others to SP6?

Any recommendations are certainly welcome, feel free to message me directly
or respond here.