I would recommend them. I have about 140hrs on a 5.7L Vortec.......had a slight problem with mixed-up heads but Raul worked it out without any problems. I would buy from them again.
I bought a 4.3 V6 long block from them. Had a little knock in it for the first half hour or so, but now the thing is smooth as could be. I think the knock was the mech. fuel pump not getting oil to it? Oh and i have about 10 hours on it now. Wish it was spring!