For me as a full time painter, lighting is one of the most important 'tools'.
I use a pair of Daylight company 2 foot, 3 tube lighting rigs, which each give 6500 kelvins of light for 42 watts per lamp.
These are not a cheap lamp (well, £120 is pretty reasonable for a lamp, if you value your eyesight I suppose) but you do get a 2 year guarantee on them which is just as well, as I have had to invoke that guarantee twice.
The rub is, that if you need to replace the T5 tubes the Daylight Company will rob you blind for what is simply a 14w low energy tube like any other. Despite the claim of 30,000 hours before a tube needs replacing, I tend to change them every 2500 hours as they do noticeably dim.
This used to be an expensive thing for me, but I found a company which supplies me with replacement tubes at under £2 each; what's more they are from quality lamp manufacturers such as Osram, GE and Sylvania (all far superior to the Daylight Company tubes) and are available in assorted light types to suit the user's needs.
I took delivery in 48 hours for ten GE daylight bulbs, delivered by UPS to my door for £21.00
If you use a daylight lamp, I would urge you to make sure you change the bulbs at least annually and to do so, buy your bulbs from www.lampshoponline.co.uk