The only real answer I can give is "maybe".
When hosting on a VPS provider it is more important than otherwise to try have enough RAM such that as much of your data and indexes (or at least the normal "working set" plus some) fit into RAM. You will be sharing the I/O subsystem with other VPS accounts that might be running heave apps on underspecced VMs so saving even a small amount of disk access can make your app much more responsive at times when other VMs are active.
The best way to test this would be install the app and database (full of test data of appropriate size if you don't have a live set yet) in a VM using one of the free virtualisation solutions, run some benchmarks against the app (or just get some users to click around), and watch how much I/O results via the relevant Windows performance counters in the VM. Repeat the tests with different RAM allocations until you find the sweet spot where adding more RAM makes little difference to the I/O load.