As an online retailer myself, this thread is quite interesting - it confirms the 2 main points I adhere to when selling products via my website - 
1 - It MUST be in stock if your site is listing it as such.
2 - Delivery must be quick.
Before I opened my shop, these were my biggest gripes when buying online and it seems they are for you guys too.
Probably only of interest to guys based in England/Europe but do feel free to check out my website - shipping is same day (95% of the time) and if its listed on my site - its IN STOCK.
My prices are also 5% less than UK RRP so for kits its probably cheaper to go with the US/Far east companies if your not in Europe but for European manufactured stuff I'm pretty competative.
OK, shameless plug over with 
 
   
   
   
 Oh, yes, I have also bought a new Tamiya HG SF Airbrush from Lucky Model - No problem with delivery at all and VERY cheap.
Lee