I just checked with a local JTAG service. they quoted me $75 ($25 more). i told them that's much more than the price i'd get at mobiletechvideos.com, and to put it in his words, he said "those sites are bull****. they will switch out your parts and tell you they can't fix it."
to that i replied "developers and people from XDA have recommended their service" and he told me "you think i don't know that?" That's where I ended the conversation. I don't trust them at all, if all they do is badmouth people they don't even know anything about.