Both the LightSheer and GentleLASE lasers work beautifully for laser hair removal. The GentleLASE uses 755 nanometer wavelengths and the LightSheer uses about 808 to 810 nanometer wavelengths.
The LightSheer, or diode laser, works a little bit deeper within the tissue. However, the additional 50 nanometers of frequency does not equate additional effectiveness in hair removal. The LightSheer also has a larger spot size; practitioners can finish their sessions faster and offer less pain for patients. (Neither of these lasers are particularly painful, especially when a topical anesthetic is applied to the treatment site prior to beginning therapy.)
I see a great efficacy with three sessions of either laser for slowing down hair growth in treated areas. The bottom line – I would pick whichever laser is more cost-effective at your dermatologist.