SQL Server - Overlapping NC Indexes, Drop Question
When two indexes both satisfy a query, you'll find that the smaller of the two is selected. Often, this means the narrower index, but it also holds true with fully duplicated, identical indexes, with the physically smaller one being preferred.
Unless you're scanning the index and the full size matters, your index tuning Spidey Sense is right. Drop IX_1 and your queries will use IX_2. Those seeks will hardly notice.