Well its more uvb than uva.
The sun emits loads of uva and that doesn't seem to hinder outdoor growers.
All uv rays are harmful in large doses as far as i know anyway.
Heres where i am going to buy the uvb tube from.
ISO ITALIA - Tubes, UVA Lamps, UVB Tubes for Sunbeds and Tanning Units
I have also heard that some people and some strains like the cold effect but i think you'll find that they achieve that by letting the grow room get nice a nd cold during the last 4 weeks of flowering in the dark period.
