they generally are hit or miss. reports of sloppy silicone and other things are not uncommon. i had pretty good luck with them. they made my 195.
the thing you have to ask yourself is- are the blemishes worth the better price?
when i went to pick up my tank many others were too. it was at a centralized location about an hour from my home.
my tank had a small nick on the corner back of the tank and it was supposed to be euro braced. instead this is what i arrived to find-
they also put that black plastic border on the tank to hide sloppy craftsmanship. i complained to the people in charge and they handed me a few dollars cash right there. i accepted it because i was on a schedule. if i didn't have a tank that weekend, i would have had to pay for another month at my old apartment...bla bla bla...
anyway, this tank was about half the price of the other quotes i got.
it was worth it to me, and i would use them again if they were able to duplicate another "half price" deal like that.