Sharepoint GetItemById, GetItemByUniqueId, SPQuery performance

Testing process:
1. Creating ConsoleApplication
2. Getting Test site
3. Creating Test scenarios
4. Run tests and measure performance

Test1: return list.GetItemById(x)
Test2: return list.GetItemByUniqueId(x)
Test3:
SPQuery query = new SPQuery();
query.Query = "<Where><Eq><FieldRef Name=\"ID\"></FieldRef><Value Type=\"Integer\">" + id + "</Value></Eq></Where>";
query.MeetingInstanceId = -2;
query.ItemIdQuery = true;
query.RowLimit = 1;
SPListItemCollection items = list.GetItems(query);
if (items.Count > 0)
{
    return items[0];
}

Results and conclusion:
All 3 tests performed about 15ms for each SPListItem, so its about readability or usability witch one to use.