Got a Slimline-3 SWM, HR34 and 3 HR25 clients when they were pretty new. Now they call the HR34 the Genie (good marketing move IMO). I have the DECA and everything works GREAT! Genie has 5 tuners. I can watch different live or recorded programs on all 4 TVs and share the Genie playlist on all 3 clients. The only improvement I could want is the ability to use trick play features on the clients without having to record what I'm watching to do so, but it's a small thing. Having internet distributed to all boxes via coax is dead simple. Can't imagine why anybody would want to make it more complicated with ethernet connections to each box, though my house is fully wired with cat6 in every room so I could easily do it that way but why mess with success?
My On Demand features work very well. Once in a while while streaming a show I get an erroneous message that there is a problem because the connection is too slow, but I just select "continue, fix it later" and it keeps playing just fine.
The only time the system bogged down was when they first pushed out the Genie update. The Genie must have been working constantly to cache all the recommended shows. The HR34 suddenly seemed sluggish. I found how to turn Genie recommendations off in the TV shows section of the search page and it started running fast again. I don't care about recommendations and with the huge library of On Demand content available, I can watch practically anything I care about, anytime. I use it a lot and rarely watch live TV. I find that I'm using the Genie's playlist less and less all the time.
I was a Direct TIVO fanatic for many years and gave them up reluctantly so I could get full HD content, but I easily adjusted to the HR34 and much to my surprise, I now actually prefer it to TIVO and the boxes only need 1 coax each, not 2. I use the extra coax to distribute my OTA antenna for FM radio now. I can also use it for OTA TV if satellite should go out, but I have never felt the need to do that. In the worst storms I get maybe 5-10 min of rain fade, max, and that is very rare. Cable outages were fairly frequent, usually involved that stupid cable van coming out, and could take days to resolve.
I have FIOS at work and I find their DVR interface lousy and the box freezes and has to be rebooted at least once a week. I just got Comcast for my mother-in-law's condo and was insulted by the gigantic 2004 cable boxes the installer delivered. They have DVI and component outputs, but no HDMI and my TVs can't complete the handshake with a DVI to HDMI adapter. Even my 2004 Panasonic plasma with a DVI in doesn't like that box. What a bunch of garbage, just to watch cable and I didn't even order DVR functions for her because she wouldn't know how to work it and doesn't care.
I am totally sold on Genie. It came to me as an HR34, but has improved since D pushed out the Genie package and it just keeps getting better. Simple hook up, simple operation, intuitive interface, medium sized, attractive, DVR box (way smaller than the DCT6200 cable boxes Comcast still foists on people), tiny HR25 client boxes ('bout the size of a 400 page paperback) which you can stick to the back of your TV, one coax per box, no ethernet (except for the 1 to the DECA)...simply amazing.
BTW, one of my clients lost it's HDMI output last week. Called D, had a new one in 2 days. Had to call to get through the activation, but that was good too. Had a rep on the phone in under a minute. She was really nice, knew her stuff and got me hooked up in a flash. She skipped the usual troubleshooting steps because she could tell from my description of the problem and my efforts to fix it that I had done a thorough job of troubleshooting. She had to restart the Genie from her end because the new client wasn't seeing the Genie playlist and it is 3 stories up in my house. The reboot fixed that issue and I was back in business in short order. The whole process took less time than it usually takes to get a human being on the phone at Comcast and most of them start with page one of their script, waste half an hour of your time and end up making you bring in the box to their horrible local office to swap it out after the nasty people there give you a bunch of crap (reminds me of the DMV). Also, I can stream my DVR content to my iPhone, iPad and computers, both home and away.
I hate cable and my life has been so much better since I got DTV 9 or 10 years ago. I LOVE DirectTV, and no, I'm not affiliated with them in any way. Just a very happy customer who has had years of fabulous service with better content and hardware, for less money than the competition since the day I switched.