Found NFC great to be honest though I have more or less done all my flying with them so don't have experience of other FTO's.
Delays in training were primarily my fault due work or the intolerable Irish wx (though people tell me that flying in our not quite CAVOK wx is good training which I don't doubt).
As well as that flying at EIWT compared to most Irish airfields has the added benefit of having to deal with a lot of traffic movements, noise abatement procedures and controlled airspace.
Like I said, no experience of Skytrace but from my experiences with NFC I can't fault them. That said, book early and often if you do want to complete your training there. They are a seriously busy operation.
All the best with the PPL.