I have two Ultras but the best value is my tasco Pro Point 2. paid about $60 from Midway and the optics are absolutely crystal clear, and the dot is perfectly round and clear. I am having problems with the new UD's (trying to buy another one) and also Milletts having astigmatism distortion through the lenses. If you shoot with only one eye, no problem. two eyes and they will give you double vision.
I also ahve an OKO sighter which is very good for about $165 (rail sighter similar to hakko and C-more).