[noggin]

• I'm not a linux pro and the RPi2 has a way bigger community with more how to's to make sure I don't bork things

Pi 2 support is significantly better than C1+ from the manufacturers. Pi 2 has an actively developed and up-to-date kernel. ODroid have confirmed that they are not planning on upgrading the kernel used by the C1+. (I asked them in their forums as one my DVB-T2 tuners is not supported)

Deinterlacing does bother me so that would go towards the C1+ hardware deinterlacing, especially when acting as both a PVR frontend and backend.

There is very little difference between the C1+ and Pi 2 deinterlacing if you run MMAL Advanced (which is GPU accelerated AIUI) on the Pi 2. However you do need a mild overclock on the Pi 2 for MMAL Advanced to work on 1080i content.

DVRing two channels while playing one or two channels would be a lot of throughput for the RPi2's single USB bandwidth

Yes - this is the biggest issue for the Pi 2. You have a single 480Mbs USB 2.0 bus (reality is less than this) to carry 10/100Mbs Ethernet and all of your USB traffic. Assuming you are in the US your bitrates are going to hopefully be a bit higher than in Europe (as MPEG2 needs approx 2x the bitrate of H264 for a given picture quality) - so this will stress the set-up more. Every channel you record or stream over the network will require double its bandwidth (once to come in from the USB tuner, again to go out to the disk or network), but channels you watch live on the Pi 2 should only require their bandwidth (as they come in an to the Pi 2 and don't go anywhere else)

If you are building a PVR that needs to tune more than 2 HD channels I'd go for the ODroid, as it has Ethernet on a separate bus I believe.

Don't need CEC since I've got the Harmony

No idea if I'll be playing/streaming HEVC, where is it starting to show up?

Mainly on illegally downloaded content. The 10 bit version is likely to be used for broadcast (but not in the US any time soon) and the C1+ won't handle that in hardware.

I only have a 2.1 setup, so I assume the multichannel and HD audio differences are moot. I would run audio through HDMI to TV then from TV to receiver using optical. The TV only outputs 2.0 over the optical passthrough so hopefully it can sort out whatever the RPi2/C1+ send it or I can set them to output 2.0 only.

I have a 3D TV, but barely watch 3D so I figure I can just use the smart TV's DLNA to play 3D if I get the C1+

I'll likely be using ethernet so no WiFi dongles

Hopefully whatever USB ATSC tuners I get will work with the C1+ with only 3.10.xxx kernel in wrxtasy's great looking OpenELEC build, according to the linuxtv list, the most common KWorld UB435-Q has a newer V3 that might only work with 3.16.xx...

This is where the Pi 2 definitely wins. The kernel support for Video4Linux tuners from Hardkernel is very patchy. I've got a tuner that was properly supported a year or two ago in the mainline V4L Media_Build, and it isn't in any ODroid kernels, and their kernel sources are such that I can't do a Media Build myself (as I have in the past on Pis)

With the RPi2 overclocked for deinterlacing, can I run multiple USB tuners on it without an external USB power hub?

You should probably be using a powered hub with multiple tuners on either the C1+ or the Raspberry Pi 2 to be honest. I have had multiple DVB-T and DVB-T2 tuners running on a Pi 2 without a hub, but I'd always recommend a powered hub for small ARM boards that are USB powered (or powered through USB-style systems).

I could run Android and play games on the C1+ too, but might not be worth it as it might take more time for me that I want to spend, doesn't seem like I can just log into my Google account and download the games I have already bought on my phone.

I haven't built linux machines before but have a little experience mucking around with Terminal on my Mac so I'm a bit concerned about this project eating too much of my limited time. So I like the RPi2 for the seemingly rock solid build, massive community with beginner friendly docs, easier to repurpose if it doesn't work out. I like the C1+ for the likely smoother running interface and CPU headroom, better power management, and possible Android. It's not much money so I might just buy the RPi2 and make sure I can get it running properly and if it isn't fast enough, I just save the Pi for another project and put the parts on a C1+, but might get grief from the wife on buying one more board just waiting for a project ...

Any advice from those experienced with similar builds?

Personally I'd split the Kodi bit from the TV backend bit and build a separate TV Headend server to run on one device, and run OpenElec on the other. That way you can upgrade and fiddle with Kodi without having to blow away and rebuild your TV server every time. There is still a lot of merit in using a cheap, old, x86 box as the TV Headend server. I've even run it on a PogoPlug though to be honest.

However I'd suggest a much better box, really, for a TV Headend combined Frontend and Backend is a Chromebox or similar. It has multiple USB 3.0 ports, GigE and high quality Intel MCDI deinterlacing and hardware acceleration of MPEG2, VC-1 and H264. Only caveat is interlaced VC-1 support is software only because of Intel's continued inability to fix their Linux drivers. No HEVC - but a rock solid box with headroom and you'll be nowhere near its limits with a couple of ATSC dongles, running a new kernel, with a decent power supply, no hubs etc. Much neater build. You'd need to add an IR receiver into the mix - but an RC6 USB dongle or FLIRC will do that