Upgrade/ Sandwich at Venetian - Rialto to Prima

[sliverslepa]

I am thinking about a $100 sandwich/ asking for an upgrade when I arrive at the Venetian in a couple of weeks. Right now I am comp'd a Rialto and I want to upgrade to a Prima suite. Anyone have any experience with using a sandwich on comps or upgrading from a Rialto to another suite at the Venetian?