The chuck had a very sharp bur on the keyway, that was easy to remove. Otherwise the machining looks great. With the chuck mounted in the spindle I measured about .00015 runout on the taper, which is about what my bare spindle measures.I also noticed that the chuck is not as hard as I would expect. It scratches easily.Indicating on the shank of a new 1/2" carbide endmill in a collet gives .0015. I removed the nut, and rotated the collet 180 degrees in the nut. I found that the runout also moved 180. This makes me think the runout is in the collet. I spent 30 minutes carefully deburing the slits on the collet inside and out and cleaned the collet. Then I measured .0006 runout on the same end mill.The set was was better than I expected, considering the price. Its a usable tool. I would be disappointed if it had cost more.I am very pleased with this set. I bought it to increase the size and flexibility of my R8 collets. I have found this easy to use (once I figured out the “trick” of tipping the collet to get it in and out of the nut). I get 0.001” TIR with various collets and tools.I did receive a “special” collet set with two 3/16” collets and no 1/2” collet. I contacted the company and within two days I had a 1/2” collet. I was very happy with their quick response time and with their customer service department.If you want a collet set that covers from 0.079”-1.024” (2 mm - 26 mm) without any gaps, you will need to purchase the metric collet set. Each collet has a 0.039” (1 mm) gripping range, and there are a few small gaps in the inch collet set.I am thinking about getting the inch collet and holder for my son. I have found this set a great addition to my home machine shop.The machining was impressive, except the key way. It is razor sharp. But mine came with .0006 t.i.r With the 1/4” collet, that magnifies to .002! That is a lot!The 1/2” collet holds to .0006 Those are my most used sizes. I’m sure the rest are just as inconsistent.I have a set of R8 collets (1/16" steps) as well as R8 end mill holders. Both of those are more of a hassle to change end mills than using on of these items. I can leave the main item in the mill and just change the collet to use different sized end mills or edge finders.I also picked up the ER32 version since I'll need to machine close to a feature rise on some items soon. With the nut being closer in size to the main body, on that one, I shouldn't have any issues. I also like how tis one goes up to a 1" collet (end mill shank size) capacity. You can also purchase additional collets, or even metric collets, for short money to expand your capability.The quality is great and I received the order on timeI haven't used this one all that much yet, but it appears to be of very good quality and the R8 fit like a glove. This will be much more efficient than removing the draw bar for each tool change.4/22/20 Update: I've now put a lot of use on this set, and it is still performing great!I noticed a review saying that the "clamping nut was not machined correctly," but I think he may just not fully understand how to properly use the item; the hole in the ring is supposed to be off-center as shown in his picture. You have to clip the collet into this piece before you put an end mill into the collet. The ring is machined in such a way that it fits into the groove on the collet and pulls the collet out of the taper when you unthread it. You can't just set the collet in there and thread it together. Hope this helps.I had to modify a D camlock adapter for my lathe to be essentially zero runout before I could even measure these, and they are, if anything, better than advertised - 1 or 2 tenths peak to peak. Haven't used the R8 chuck yet.Very hard metal.You'll have to make things very clean to get the quality these have built in.They had a problem with their machining setup. The nut is easily machined 1/8in out of round. When the collets are placed in the holder, the nut hits the collet edge (as its out of round) and does not allow the collet champher to seat to the tool holder champher. They MUST know they have a problem but are still selling these? One other person on here has indicated the same problem. Don't purchase these until they QC their stock. Guess the only one that makes out are the shippers... lots of shipping cost for nothing.