A poncho and a shelter ask fabric to do different things. The M-Tac Tactical Rain Poncho - Army Military Poncho Shelter - Waterproof Ripstop Camping Hiking Outdoor Hunting Rain Ponchos is marketed for both, with a waterproof ripstop description that makes the exact construction and attachment arrangements worth reading carefully.

I'd buy it first for the job I'll use most often. If rainwear is the priority, its fit over clothing matters more than a shelter arrangement I may never use.

Features in the Description

Rain-poncho format.
Ripstop construction wording.
Waterproof description.
Shelter positioning in the product title.

Verify the dimensions, hood arrangement, and any attachment points for the selected version. A poncho needs enough room for the intended wearer, while a pitched cover needs enough area after the edges are secured.

Wearing It and Pitching It

Try the poncho with the pack or jacket you'd normally have on. Loose coverage may be convenient, but it can move while you're walking and may leave areas exposed differently from fitted rainwear.

For any shelter use, follow the actual instructions and identify the extra support pieces required. A product pictured in a suspended arrangement doesn't establish that every cord, peg, or support is supplied.

The Multipurpose Compromise

The attraction is carrying one item with more than one possible arrangement. The limitation is that you can't wear the poncho and leave it pitched over your equipment at the same time.

I'd compare the M-Tac when that flexibility fits a deliberate backup plan. If you regularly need rainwear and a shelter simultaneously, separate equipment is easier to manage. The sensible reason to choose it is a documented, usable dual role, with its real dimensions and setup requirements doing more work than the tactical styling.