You can't always tell from a product photo, but there are cues. Small battery capacity is a red flag. A device that's advertised as 'ultra-portable' might sacrifice battery life. Look for a capacity of at least 400 mAh.

Another cue: no airflow adjustment. If the device has a fixed airflow and doesn't mention the draw type, that's a gamble. Also, check the wattage range. If it's very low (under 7W), it might not vaporize thick CBD oils well. You want something with a bit of power to handle different oil viscosities.

And read the user manual online if you can. If the refill process involves a syringe or weird tools, skip it.