Well they are not very good at all. ..I was trying out my new x2 and I must say I was very unhappy with it. I never got a good focus and the very few times I did the photo was fogged and blurred...better luck next time I guess..
These are at 150mm w/o x2 since it wasnt working out at all..

The first 2 I dont know the names of these birds so maybe someone can chime in on an ID.

http://i103.photobucket.com/albums/m126/harmonyrising/Photography/birdedit3.jpg
http://i103.photobucket.com/albums/m126/harmonyrising/Photography/blackbirdedit2.jpg
http://i103.photobucket.com/albums/m126/harmonyrising/Photography/blackbirdedit.jpg

http://i103.photobucket.com/albums/m126/harmonyrising/Photography/geese1.jpg
http://i103.photobucket.com/albums/m126/harmonyrising/Photography/geesefam.jpg

First is a Cedar Waxwing they are lovely birds we dont have many here but the odd time they do show up, but almost always when i dont have a camera with me lol .
Second is a Redwing Blackbird we have lots of them here sadly there is a hunting season on them here ,but i have never seen anyone actually hunt them so thats good.

As for your 2x there is almost always loss of quality , it has to do with lost stops of light . I think Loupey and Bev use 1.4x ,i have a 2x that was given to me and to be honest i use it very rarely but under the right lighting conditions they do work . But i have searched the net for 1.4x combo photos and the appear to be the best as far as using teleconverters and proof of this is Bev and Loupey`s work and im sure that many more users use the 1.4 X also. Hope this helps you more than discourage`s you .
As for your photo`s here i would say they are good for the first use of your 2X, like i said you have to know which conditions are best tu use it with .

As long as you learn from the experience, that's what counts.

I have only the 2x TC. Because there is a loss of stops and quality (even with the best TC), just remember that you must learn when and how to use it. If the conditions/lighting is marginal with your prime lens, then it will be unsuitable with your TC. If the resolution of your prime lens is marginal, the combination with TC will be unacceptable.

Try practicing on bright, cloudless days. Once you get the hang of it, you can practice in lower and lower lighting conditions.

Thank you Knight for the IDs.. There was a group of the Cedar Waxwings flying about and 2 of them stopped just about 10 ft from me.

Thanks Loupey for the advice
It was really cloudy and over cast today....I will try it out again in a sunny day and see how it works out then.