Precise Bits makes reducers they claim really work: http://www.precisebits.com/products/equipment/collet_reducer_500.asp
According to the Precise Bits web site, all other reducers are "made by Satan"
Funny, I thought he had an exclusive deal with Harbor Freight.
I doubt they include the Elaire Corp. collets in that. They work quite nicely and are very well made.
They didn’t say that about collets at all. They said it about collet reducers. 
From http://www.precisebits.com/news.htm :
“After years of telling our customers that collet reducers are made by Satan, we decided to see if we could design and build one with the same level of precision and balance as our ER style spring collets. While there are some inherent differences between tapered collets and cylindrical collet reducers, minor tweaks to the inter-leave geometry enabled us to reliably produce reducers with low TIR, uniformly high clamping pressures and virtually perfect balance. Best of all, no Satan.”
Sadly the Precise Bits reducers are all for 1/2" routers. The DeWalt 611 is a 1/4" router.
Good point. I wasn’t shopping them, just pointing them out, and hadn’t noticed that. Sorry. 
Although we are currently out of stock, we do carry a very nice precision 1/8" collet for the Dewalt
We should have them back in stock by the end of the week.
-Edward
FWIW, those have been listed at the link I provided for a while.
They’re also at: http://www.shapeoko.com/wiki/index.php/DWP611#Collets_and_Nuts which arguably is where we should collect information on using these.
I just wanted to say that I did buy the Precisebits collet system. I am totally pleased with their ease of use and precision quality. They are superb albeit pricey. But you get what you pay for and it’s comes with nice accessories.
I especially like the wrenching system over have 2 flats.
+1 to the PreciseBits collets. They are well built and work great.
+1 PreciseBits collets.
mark
No love for the Like button?
too much like FB. 
In addition to Carbide 3D there are two other suppliers: http://www.shapeoko.com/wiki/index.php/DWP611#Collets_and_Nuts
I’ve used this reducer with success, albeit I’m not machining metals (yet):
The one C3D sells works very well. I actually use 1/8 tools more often than 1/4 on my XXL and have had no trouble at all.
List of these on the wiki and a cautionary link: http://www.shapeoko.com/wiki/index.php/Spindle_Options#Adapters
I view them as a source of runout and another potential point of failure. Avoid.
The 1/8" collet in the Carbide3D store seems to be out of stock every time I look for it.
Are they expected to be restocked soon?
+1 on the collet from Elaire Corp. That’s what I’ve been using, and so far so good. Not sure what the runout is on it, though.