Hilton location is convenient but the hotel is badly in need of updating. I was there last summer (for a conference) and the rooms have major sound proofing problems. Both noise from other guests (most of whom were leisure travelers who didn't have to get up at 7 a.m. for conference talks) and from the trains were issues.
I stayed an extra day and moved to the Historic Anchorage Hotel a block away and that was infinitely better.