ViparSpectra original line of LED grow lights belong to the Reflector Series. These lights come in a range of sizes in the UK from the small 300W LED grow light, the V300, the medium-sized 450W and 600W ViparSpectra plant lights (the V450 and V600, respectively), to the big 900W devices, the V900 and the R900.
The ViparSpectra grow lights stocked here in the UK are well-built fixtures sporting 5W LED grow bulbs of a decent pedigree (the bulbs are manufactured by the US company Bridgelux and the less well-known, but still reputable, Taiwanese company EPILEDS Technologies Inc (not to be confused with the Epistar goliath)). Apart from the 300W (V300) LED grow light, all the bigger lights in the ViparSpectra range are partially adjustable in that they have the ability to control the type of lighting output that is either best for vegetative growth or for flower / fruiting production. For instance, in the case of the 450W (V450), the vegetative growth setting uses approximately 100 Watts of electricity with just under half the bulbs on. For flowering and fruiting, turning on both the bloom setting together with the vegetative lighting bulbs on the LED grow light most likely provides the best flowering / fruiting yield from plants. Under these conditions, all the LED bulbs are on and the light draws approximately 200 Watts, equivalent to two incandescent bulbs of yesteryear. Turning on the bloom setting alone without turning on the bulbs for vegetative growth is unlikely to produce a higher yield as plants still need the blue wavelengths during this phase of their life cycle as well. However, having the ability to turn on just the flowering bulbs increases the versatility of the ViparSpectra LED grow lights, allowing them to be used instead as just flower or 'bloom' booster additions to any other grow lighting that you may already have.
One of the unique and useful features of the ViparSpectra grow lights is the ability to 'daisy-chain' individual lighting fixtures together. By plugging only one light into the mains electricity and then daisy-chaining subsequent lights in series off this initial light, you end up using only one mains power socket. This is particularly useful if you have (or intend to have) a large growing setup with multiple LED grow lamps, as it becomes much less cumbersome to deal with all the wiring. However, it should be noted that this feature is understandably absent from the bigger 900W (V900 and R900) LED grow light models that are available to buy.
Update February 2021: Currently, there appears to be two versions of the Reflector series grow lights from ViparSpectra, those with the power daisy-chaining feature and those without. The V300, V450, and V600 lights sold via Amazon UK, no longer incorporate the daisy-chaining feature. However, the same 450W and 600W versions of the Reflector series lights sold directly through ViparSpectra's own website, still come with the daisy-chaining feature included.
ViparSpectra lights produce relatively little heat which is adequately dispersed by the internal cooling fans, however, using them in an enclosed space like a grow tent will raise its temperature a little which may then require ventilation. As for noise levels, like other higher quality LED growing lights, fan noise is hardly perceivable when used within a grow tent or similar, but the fans are sufficiently noisy that you would not want to use them in any exposed personal living space. One other point to note is that the lights are very bright and some users have recommended using specialised eye protection when working under their glare to prevent any risk of eye irritation and headaches.
The only minor negatives with the ViparSpectra lights are the lack of coverage in the UV end of the spectrum, and the inclusion of white LED bulbs. The need for UV for plant growth is debatable as many-a-plant has been grown indoors successfully without UV. However, plants have evolved over millennia in the presence of constant and powerful UV from the Sun and some internal plant processes may occur better under UV wavelengths. As for the presence of white LED bulbs in the grow lights, if you want to know why we prefer not to have them, then see the review of white LEDs here. However, this is not a deal-breaker by any stretch as plants have ultimately evolved under 'white' sunlight and the majority of consumer LED grow lights incorporate white LEDs to ensure that they are covering all the essential elements of the visible light spectrum.
The ViparSpectra brand itself is owned by the Chinese company, Shenzhen Bailuo Technology, that primarily specialises in selling LED lighting. The company is super-responsive and it is clear from both the quality of their products and the support they provide that their aim is to build a good reputation amongst their customers, which up until now, appears to be succeeding. Once again the ViparSpectra lights are available on their own website as well as on good old dependable Amazon through its FBA program meaning that the LED grow light panels are stocked here in the UK. Overall, given their quality, features and relative low cost, these LED grow lights are highly recommended.
The ViparSpectra Reflector Series LED Grow Lights in the UK
** Lights that are daisy-chainable only have this feature if bought from ViparSpectra directly.
Equivalent versions of the lights on Amazon UK can not be daisy-chained.