Hi. In my company we are plannig to migrate our application based on Websphere 6.1 + JDO (Xcalia implementation) to Websphere 7 + JPA.

I'd like to get some opinions on which JPA implementation use

We've doing tests of different JPA implementations. Hibernate and OpenJPA. Our results show that Hibernate is better in terms of performance but i'm worried about how well will hibernate JPA integrate into WAS 7.0.
Another thing i'm worried about is the support we'll get from IBM if we choose OpenJPA. What kind of support does IBM offer? Are there any SLA's? Which tools does IBM to offer support (bug tracking,etc.)?

Thanks.