Considering a pair of Wilson Yvette speakers

I recommend you go to ASR (Audio Science Review) and check out the review/measurements of them first before making a decision. If not there, then go to the Stereophile archives and look for John Atkinson's test report. Buying speakers without measurements is foolhardy!

The Yvette speakers are highly resolving and dynamic speakers very neutral in their presentation. What are the electronics you will be driving them with... and compared with what the dealer was demoing them with. 

I had a pair of Yvettes for a about four years.  Amp matching will be key as @ghdprentice mentions.  They were really good with D'Agostino power, but room placement is on the finicky side. 

If you listened to them and liked them, measurements are irrelevant except their sensitivity, i.e.: does your amplifier have enough power to drive them properly and if it is a good sonic match. How a speaker sounds is much more important than how it measures. You might want to take your amp to the dealer and have him hook it up to the Wilsons and see if you still like them.