• Platform size and load — ORSHA15 and ORSHA21 are compact bench units; ORSHA344 and ORSHAMP3 carry large or stacked platforms for high throughput.
• Speed range — from about 50 rpm for gentle mixing up to 500 rpm on ORSHAMP3 for vigorous extraction.
• Orbit — a larger orbit moves more liquid in a flask; a small orbit suits plates and shallow vessels.
• Clamps and mats — flask clamps, test-tube racks, separating-funnel holders or a non-slip mat — the platform decides what the shaker can hold.
• Duty — continuous running matters for overnight extraction; check the rating, not just the top speed.

If the protocol runs at room temperature, an orbital shaker is the right answer and the cheaper one. The moment a defined temperature is part of the method — growing a culture, holding a reaction at 37 °C — you need a shaker incubator, because a shaker in a warm room does not hold a setpoint. For single tubes, a vortex mixer is faster than any platform shaker.