Just fine when

you buy only for wintering the lamp.
Among the shortcomings of the previous speakers, that does not keep the lamps long, I can not say anything, they have also a 3 Euro switch hung and light to assist daylight 0600-2000 clock since purchase.
Have already new shoots in my Bonsai's. Because of the earth or the air I can not judge.

The heat dissipation of the light source is enormous, measured after 24 hours duty, about 64 degrees with IR measuring instrument on the outside of the lamp housing.
That was me a bit too much, so I've been working the case.
On top taken off the cover at the cable gland and 5 mm holes drilled at a distance of 3 mm to each other at the edge of the lid.
And the lamp neck with 3 openings each 1cm x 5cm edited.

The temperature after 24 hours of continuous operation at 28 degrees then lay.

All the cooler the operation, the longer holding the bulbs. I suppose time strongly.

Maybe me the lamp disabuse if it is then broken times, comes an update.

MFG Robert