I visited a Dhammakaya temple when I was a monk, so I'll ramble on a bit about that.
It's odd that it would have ever come up since I was ordained at one of the better-known temples in Thailand, Wat Pho, so strange I'd be sent to visit a completely different sect during the same ordination. I expressed an interest in meditation during that time--it really seemed a natural part of the program, and of course I was there based in part on prior interest in Buddhism--and I'd been visiting a meditation center at Wat Mahadat since that was set up for foreigner instruction (http://meditation-centers.blogspot.com/2010/05/wat-maha-that.html).
My monk teacher / master (no good way to put that, really) wanted to send me to a country temple to study meditation as well, but didn't want me to need to travel out to Isaan where that normally takes place (or there's one place--temple, center--in the South, I think), so I visited a temple out in the country that focused on meditation, but one that wasn't very far, in that different sect.
About Dhammakaya, that temple wasn't huge like the one in this discussion, but it was nice enough, and growing fast. They emphasized donations, and sales of amulets, talk about relics (parts of the Buddha's body they came by through magic, from angels or whatever), and mixed in a bit about other magic in their teachings that ended up relating to revenue streams for them. Most was about amulets but there were strange things going on with magical statues as well, maybe not for sale but offered to the public for donation, not a lot I really heard the full story on.
The lifestyle was mostly ordinary, and the monks seemed normal and well-intentioned, but some things were odd. Meditation was completely different, guided meditation, someone talking rather then a more typical inner focus, with lots about visualizing crystal Buddha images. You would get certificates of attainment for saying you had experienced certain things meditating, like an informal degree. None of that really contradicts the teachings of Buddhism, it's just not a close match. Of course some would say it does contradict; I'll say more about what I meant by that.
They also talked about heavenly realms in ways that came a lot closer to contradicting standard Buddhism, but really it's not as if there is one set of clear teachings so that it's easy to flag what is wrong. The Buddhist cannon is huge, and it's my understanding that it internally contradicts itself (not something Buddhist scholars tend to make a big deal of, but that's my take). As an example, in some passages the Buddha is clearly saying he's not teaching there is or isn't rebirth, that people come back as another person, but in others he clearly endorses the idea, implies it as a given.
So the parallel with materialistic versions of Christianity seems really accurate to me. They stretched the teachings of that religion, which I didn't tend to see well-described as a religion in the first place, not the kind of thing you want to say a lot about while ordained as a monk, and more or less threw the normal focus out the window to embrace material concerns instead. Monks can't own any money in any versions of Theravada Buddhism, but of course that's not how the practice works anyway. They charge monks for expenses like electricity in some Thai temples, enforcing that they need to own some amount of money. The rationale is that they do receive money during ceremonies, people give it to them, and without any limits monks could use any amount of electricity they choose, could waste power all they like. Of course they all have cell phones too; kind of a separate issue.
The problem with Dhammakaya isn't about monks having cell phones (or laptops, or expensive sunglasses, or traveling a lot), it's about some being fabulously wealthy, and the temples themselves being very commercially oriented endeavors, altering Buddhist teachings to support that.
What is it with the Irish?!. . . http://www.bangkokpost.com/news/general/778461/irishman-bent-on-suicide-jumps-to-death-at-suvarnabhumi
Another article here: http://www.ibtimes.co.uk/thailand-irishman-jumps-his-death-bangkok-airport-after-being-unable-afford-flight-home-1530815