Hi Goody,
Will you be using this for private or commercial use?
I've most flown the Lycoming LTS Super D's and D2's. I've found them to be very good engines and burn less fuel then the Arriel (depending on how you fly them).
As you know there are many variants of the AS350's, so it really depends on what you are looking to do with it, you've chosen a good airframe in my opinion.
Good luck.