Worth to try 5.2? (had problems with 5.1)

Hi.
about 2 monthes ago I was trying 5.1 on IBM x345 server (Xeon with HT, Intel
PRO/Gigabit adapter, Fusion MPT SCSI) and had the following problems:
- with ACPI enabled: hang during boot process on keyboard detection;
- with ACPI disabled: boot ok, but permanent kernel panic in ufs2 code on
formatting disks.
Server runs heavy threaded application (oops web cache), up to 1000 active
threads, so I think 4.9->5.x upgrade should give performance boost, but worring
about stability. 

Thanks in advance,
Andriy Korud