Whilst there was a time that OTT was the bees knees (they are still good) – there is now a dirth of daylight bulbs on the market…that is probably what you are going to be after. They will give you a more "true" representation of the colors you are using.
However, a true and accurate accounting of paint colors is not always ideal. If you always game under florescent lights (or any other limited spectrum lighting) and your figures are not entered into painting competitions – you should paint under the type of light you play under. That will give you a true and accurate representation of what the paints will look like most the time. Others prefer to use a cooler light, since most reference photography is attempted to be taken under an overcast sky (not always possible though). The cooler light replicates the overcast conditions…so when you take the subject out into the sun – it looks like it should.
Anywho – on to the light linked to itself, the easiest way to get a handle on things is using color temperatures. The one you linked to is listed as 5500K. When we compare that to a color temperature scale we find that it is right at "Sunlight at noon"
That will work well enough if you are looking to replicate natural sunlight.
The other issue though is the CRI (color rendering index), which isn't listed on the HD site for that particular bulb. You want a CRI as close to 100 as possible. Broadly speaking, florescent and LED lights are not good at providing a high CRI (though aquarium supplies have actually done better than normal domestic lights in this regard). Halogen and incandescent lights usually are close to 100 due to the nature of how they generate their light.
Keep in mind though, after about a week – the manufacturers color temperature no longer applies to fluorescent light bulbs. You will also need to pay attention to the curly cue and dust, as that will cut down on the quality of the light significantly as well.
With the dimmer switch – make sure it is rated for fluorescent lights though (and the bulb is rated for dimming as well). I would probably just swap the dimmer for a switch and then put them back when I move out.
For me – I paint under normal halogens. They are the same lights I game under and they are the same lights my miniatures are displayed under. They get a little warm, but that comes in useful to accelerate paint drying. I have a selection of other bulbs for customer jobs…but most of them get confused in regards to color temperature and CRI.
If you do a bit of follow up research on the color temperatures and CRI, you can determine whether or not you think that the lights are that important to your painting style and needs. If they are not – use whatever you have handy. If you really think you need a "special" light to paint under (probably less than 1% of those who paint miniatures) – hitch a ride to a lighting store, and have them do it right. If you put a high dollar bulb in a room with yellow walls (or beige, or red, or any color other than photo white)…you will get the same results as using a discount bulb from the local Quicky mart.
