I use half-unit pens for both Levemir and Humalog. The Levemir one made the most difference, but both are a great help. Definitely do airshots, these pens work the same as whole-unit pens so need the same treatment. I guess the 'junior' name and colour schemes are due to small children on average needing lower doses.
When you collect your insulin, always check before leaving the pharmacy that they've given you cartridges and not pre-filled pens. If they give you the wrong one its an official error which they should record, but I find it happens every few months.