I've been a using tubeless wheelset for about three years.
Shimano DuraAce /Hutchinson Intensives/Stan's:
I found the combination rides very well. It's possible to run the tyres at a lower pressure than you might be used to. I currently run mine at 105psi against the 120psi I use in regular road tyres.
Despite the lower pressure the wheels roll very well. In fact, on downhills I tend to drop away faster than most other riders no matter the excellence of their wheels. The lower pressure also provides an extra degree of comfort/smoothness which is welcome. The lower pressure doesn't seem to impede the wheels' rolling characteristics.
In this time I have had one flat. This was a 20mm slash caused by a broken bottle. Stan's couldn't cope with that (although it did try) so I got home with an inner tube and a tyre boot.
That's not to say that I haven't had more minor punctures. Most tubeless tires show evidence of punctures by the end of their life. It's just that the sealant has done its job. BTW, the sealant isn't required to seal the bead in a good installation. Its job is to cope with punctures.
These tyres do require maintenance. You will need to replace the sealant at least once a year and initial inflation requires a high-volume air source to seat the tyres, so it might be a job for the LBS.
If the DuraAce wheel is too rich, there is also a Shimano Ultegra wheel which is also very good and virtually half the price. It is also possible to run non-tubeless tyres and rims as a tubeless wheelset via a Stan's conversion, but some combinations are inadvisable. Consult with your LBS on this one.
Other issues includes the price of tubeless tyres. These tyres are only 60% of the US price in Europe. Don't ask me why ...