Hi everybody.
I stumbled over this forum recently. It seems to be a very comprehensive source of knowledge and experience. So I was wondering, whether I will find any other Thunderlaser users here.

To me: I am the creator of the first Mini-Fablab in Zurich, Switzerland. The fablab has a lasercutter, a 3D-Printer and a cutting Plotter. Unfortunately not yet a cnc mill.
The lasercutter is a Thunderlaser Mini 60, the 3D printer is an improved PrintrBot clone and the cutting plotter is a Silhouette Cameo. The first machine I wanted to have in the fablab was a lasercutter (see www.funlab.ch, my website is in german though).
So here some thoughts from me regarding evaluation and experiences with my Thunderlaser Mini 60.

Evaluation:
I was looking at Epilog and Trotec lasers. In Europe these are machines very common. However, for my non commercial fablab much too expensive. So I was looking around for a cheaper chinese machine. In the internet you can find machines sold by some agents for around 500$ already. I encountered mainly two problems with such machines. Either they have a very small work area for cutting/engraving, not much power such as 30W or 40W or strange software with very limited function to work with the laser. And for these cheapies I found many many frustrated users which reported a lot of problems.
So I found a German forum with about 20 Thunderlaser users with a lot of positive feedback for these lasers. So i started to gather more information from their website and finally asked for a price. The name of the person I communicated with is Ken, a very friendly Thunderlaser salesman. He is very responsive and I got all relevant Information within a few days. As I liked the price I ordered the Mini 60 with some add-ons. The price was not in the range of the cheapest machines, but other users have assured me, that the components and the buildup of the machine are much better and well worth the price difference.

What to order
I decided to order the Mini 60 with a motorized table, autofocus sensor and red-dot pointer. I also added the rotary device, which I have used seldom so far and the CW-5000 water chiller. The reason for the chiller versus a simple watertank solution was, that from other forums I learned, that stable temperature ensures consistent quality of the beam and increases life of the lasertube. The CW-5000 is not made by Thunderlaser but could be ordered through Thunderlaser.

Manufacturing and Delivery
My Mini 60 was not pre-built but they started to build my machine immediately after they received my payment. I did not pay using Paypal but made a normal bank to bank money transfer, which worked without any problems. Deliverytime was 3 to 4 weeks later. I decided to have the machine shipped by DHL airfreight directly to my house door. I think the machine left Hongkong on a Monday or Tuesday and On Thursday it was delivered in a huge wood box of about 130Kilos (see: http://funlab.ch/blog/?id=xh163nak )

Setup and first experiences
After unpacking and moving the machine into the fablab I had to position it on a self constructed metal stand, had to fill water into the chiller and connect it to the laser, observing the rigth flow directions. Otherwise the laser's control program does not start the laser because of a "no water" error signal from the flow sensor. Then mount the exhaust tube to get the smoke etc. out of the laser. Then add the USB cable and connect it to the computer, install the software with driver and coreldraw macro and give it a try. By now, they deliver laserGrav as the Software which communicates with the laser's DSP controller. 11 monthes ago mine was delivered with PHCad.
It is possible to use the laser with PHCad or laserGrav only but it is more practical to develop designs in Coreldraw (certain versions only work) and then hand it over to the PHCad/laserGrav software with one click on a button, installed by the macro. In short, the machine worked without any problems from the start. The installed machine looks as can be seen here: http://192.168.1.10/blog/?id=4n2e5600

Longterm Experience and Maintenance
After some weeks, the CW5000 water chiller's pump stopped working. I contacted Ken and he organized a replacement pump, which I installed myself. This was much quicker and easier, than shipping the chiller back to china and wait for a replacement. This took only a few days until the laser worked again. Nothing to pay for that, was a garantee replacement. Over time the laser started to make some random problems. From the symptoms I described and forwarded to Ken, the Chinese specialist concluded a memory problem in the controller. I got a replacement controller sent to me immediately. This one is still on its way to me. I will have to replace it by myself, which is ok for me. But you have to keep in mind, that there is no service organisation here (at least in Switzerland) which you can call in case of a problem and who will fix the laser in hours. This is the drawback for the good price you get with a Thunderlaser machine. On the other hand this is not a problem for me, because I have the necessary skills to do the replacement. Exchanging the controller or the lasertube is not really a big challenge for persons having some mechanical and electrical skills.

Overall satisfaction
I am very pleased and happy with my machine and can recommend it. It has a good price, is good quality and has very responsive and helpful people in China to help in any phase of the process of buying, installing and using their lasers.

Too positive ?
I am only describing my personal experience with Thunderlaser related to my Mini 60 desktop laser. And no, I do not have any business or other relation to Thunderlaser. I am a Fablab guy and help all kind of people to learn about digital fabrication. Right now I am busy to build the second 3D-Printer, a dual extruder PrintrBot clone.

Hanspeter