OK so I have just orderd this thing for about $60 off aliexpress and for the price it works surprisingly well. I have to say I was a little worried being that I had to order by paypal due to the fact I needed to finish off 2 visa gift cards I had laying around. but to my luck herocloud wasn't a scammer and I got my order nearly 3 weeks later in working condition no less.
that said you may want to buy a good quality mini hdmi cable for it just encase because there have been reports of people getting bad ones.
SET-UP
I orderd the mini pci-e version which is a bit inconvenient but still relatively easy on my lenovo G410. I just removed the 2 screws hiding behind the battery and slid off the bottom panel. then very carefully removed the black and white cable from my wireless card removed the screw holding it in place then slide the e-gpu's mini pci- e card in the slot and put the screw back in. the screw they usually use is tiny so I highly recommend using a wide tipped screw driver to reduce the chance of stripping the screw.
also be sure you have a lot of desk space the cable is about 6ft and about as wide as 2 sata cables so it isn't too flexible and won't stay flat if at a bad angle. obviously you won't be able to put the bottom panel back on but I say that's a good thing because you can get better airflow with a laptop cooler which means less chance of thermal throttling on top of the lower heat from not using your intel igpu.
one last thing to keep in mind before I move to the main adapter is the fact that the mini pci-e slots on some laptops are white-listed and may only work if the wifi card is inserted. in which case you have a few options.
1.hot swap with your wifi card while windows is booted.(risky)
2. mod your bios or download a custom one if you can find it.(safer but complex)
3.download nando's setup 1.30 from techinferno.com (easier but still need to be an advanced user)
method 3 also has the ability to unlock advanced features like enabling nvidia optimus if you happen to have an nvidia gpu. so you won't need an external monitor. on some older laptops it can even change the mode of your mini pci-e slot from pci-e 1.0 to 2.0 or from x1 speed to x2 link mode on some higher end laptops.
on a pci-e 2.0 x1 link you can expect about a 20% loss in performance which means a gtx 980 is exactly as fast as a 980m. not to mention older gpu's are still 20-40% faster then their mobile counterparts on top of giving you the option to upgrade later.
now on to the main adapter 1st thing you need to do is insert the gpu into the slot which is pretty straight forward since it slides right in but some pci brackets may keep it from touching the ground so you may need a book or something to raise it higher or better yet remove the bracket entirely.
next thing you need is to power the thing which can be done one of 2 ways. you can buy a dell power brick (sold seperately) or you can use an old power supply which is what I did.
the package comes with a 8 pin Y-cable that has a 4pin cpu connecter and a 20pin connecter with only 1 ground cabel which is only needed to start the psu. the 20 pin connecter is a bit of a tight fit if your using a 24pin adapter so it will take a little bit of force to get it to slide on.
that said you don't really need to connect it if you don't want. you can always use a paper clip to connect the green wire to any black ground wire to start it. you'll know it's stared when the green led lights up. (if the led is blinking be sure to check your connections as this means the power isn't stable.)
it also comes with another 6 Pin Y-cable that can be used to power bigger gpu's.(be sure not to connect the psu to the 6 pin molex it's power out only.)
once it's powered on and you boot into windows if every thing works you should see that you have a new display adapter in the device manager. it may or may not auto install the driver but it didn't on mine. ether way windows update doesn't always have the latest gpu drivers so you'll definitely need to download and install them if you haven't already. if the driver doesn't recognize your gpu you may need to manually install the main driver through the device manager first.
now that you have it installed it basically works like any desktop gpu. unless your stuck using the hot swap method. you just need to shut down to remove or reinstall the card to make it work and the card must be powered on before the laptop.
the only draw back I've found so far is that it's difficult to turn the laptops display off while using it because intels display manager disappears.(don't worry it comes back when you remove the gpu)
that said it will work while the lid is closed you just need to make sure you don't have sleep on lid closed enabled in your power options and you may need to go into advanced settings and make sure the pci devices aren't set to sleep. it should be noted that extended display works even if you use an AMD card so you can still use it that way if needed.
conclusion:
sure it's not for every one but it's a whole lot cheaper solution then the latest alienware and if you happen to be one of the lucky SOBS who have a thunderbolt port or 2x m.2 slots it works even better. hell even if you don't have those ports you can get a $450 laptop with an i5-4200m and still get pretty close.
will it enable you to play crysis 3 with ultra settings on the road No . but if you need a small setup to drag to lan parties or just wan't one flexible system that dose it all there really aren't any better options out there yet.
mini-itx builds may be popular but they offer no practical way to attach a battery and mobile gpus are highly lacking in upgrade-ability. the only known laptops that have such a feature currently are the lenovo y500 and y400 series which use ultrabay technology but even those aren't as cheap or as powerful as this.