I saw some other reviews and was skeptical since they mentioned a few things. I decided to buy it anyway and am pleased so far. I will update this review later on with anything I feel is necessary.First, the primary review I saw complained about the beeping. Well, in the instructions it says, "the unit will start to beep after 30 minutes to remind you the time period is done and to take it off." So, whoever gave that one star review must have not read the directions and the suggested time to use it. It does not however, just beep constantly from the moment you put it on it is silent ... until you've worn it 30 minutes. By the way it has a head sensor so when you plug it into the battery pack it does not come on until you put it on your head.Also, some reviewers noted that it flashes and other caps do not. Of course it flashes as you use it because you have to wear it 30 minutes. If it didn't flash quickly, then the laser diodes would heat up too much in that 30 minutes and ruin them from constant output. The flashing is not really apparent to me since it is on my larger male head and barely any light / flashes emitting from it to reflect on anything you are looking at. Unless of course you have glasses and see it flashing off of them or are holding a ipad or tablet at your chest. As one other person stated, the flashing could have an impact on someone with epilepsy perhaps, so please be aware. If you have a medium to smaller head, then more light would come out around the edges from your skull but you could just not use the cap portion and tie a bandana around it instead and no light would be seen at all.Some others spoke about the time being 30 minutes and much longer than caps that work in less time. Well, those caps that work in 6 minutes have a little over twice as many lasers and cost 6x as much. More lasers means less working time. However, personally I got this on sale and with a coupon from Amazon so less than $300 including tax was a far better choice to wear it 30 minutes than spend $1000-$2000 and wear one for 6 minutes.Finally, lasers do heat things up of course. So, your head will tingle ... with this cap or any other laser cap. As one other reviewer noted, there is no way to turn it off from the power bank, but why would you want to turn it off while you have it on your head? If I was standing there talking to someone that just showed up at my door, I personally wouldn't leave it on. It automatically resumes the time of 30 minutes if you have it off less than 10 minutes. Otherwise it starts the counter over again. Also, it does not fit snug so you can't take it jogging, working out, or gardening, etc. None of these caps are going to be snug fitting for much more than walking around your house. I am wearing it as I am sitting here typing this and that's the reason it is made to be portable. You could also cook dinner with it on or brush your teeth, but I would personally keep it away from water and heat. Mainly it should be worn while on your computer, watching tv, walking in your house, or stepping outside for a few minutes to get the mail, etc.I just got this so I can't speak to the efficacy of it yet. I am also doing derma rolling once a week, minoxidil, finasteride, head massages, non-sulfate shampoo (not a super expensive one) and a good multi-vitamin with vitamin D, biotin, calcium, etc. It will be difficult to attribute just this device to hair growth with an entire regimen. However, for the price on this particular unit, its worth the money and has a high quality build. As one other reviewer said, the power bank is standard USB A so in a few years once it wears out, I can just get another one as long as I protect the cap and it comes with a nice hard case. I would recommend it so far since I don't think spending tons of money is justified on all of the above types of treatment. Some people spend $50-$100 / month on special shampoos which barely sink into the scalp after 5-6 minutes left in, special vitamin / gummies, (plus minoxidil / finasteride for those that don't have medical issue from them or reduced dosages of them) and super expensive laser caps.The issues I found with it are like the other reviewer said, its a larger cap to accommodate larger heads as well as smaller ones. The cloth cap part itself is very tight fitting at first, on the inner semi-rigid laser cap so putting it on and off is tough and you have to take them apart to put it in the case for proper storage / travel to prevent damage, which is a good idea for the amount of money spent. The last issue I perceive is that the manufacturers website says you have to buy it from their site to get the warranty and they aren't even advertising it there, only here. One other reviewer noted that the manufacturer honored a warranty and its a good one at four years, if in fact it would get honored, but I'm not sure about that. I think since its being sold directly from the manufacturer here, that the four years would be excellent and probably honored I'm guessing.To summarize, I think its the best value for the money with 108 lasers and the $300 cost range.