The study was linked above, but I can vouch for Asus reliability. I've owned 2 of their laptops, and have used countless amount of their motherboards in systems I've built over the years. Their notebooks are built damn well, and I haven't had a single problem with their motherboards.
It looks like the transformer is selling well; amazon, bestbuy, and newegg are out of stock (at least for the 16GB model that i've checked). Based on what I've read online, people are having a hard time finding them in B&M stores as well. Of course we will need to know how was was actually distributed to retailers to get a complete picture, though I can't imagine its too big a stock considering the component shortages.
I'v used 2 of their motherboard and both died, they may have a good spec sheet but their reliability is questionable and their customer service is woefull enough that i wont consider any of their products as long as their are other companies willing to compete for my cash.
As for the Transformer, Asus aside, it's just not for me and i don't think many people are interested in an Android notebook. HP sold out quickly then we found out they only produced 5000 devices, we will have to wait to see if the number sold is smooth, large or small.
As an aside, if these companies releasing tablets think they can take on the iPad 2 then why not release them in countries where there is no iPad 2, Finland, France?, Japan for exmple. They can build up some buzz, get good PR and ramp up production before bring their product to the English speaking world.