I believe the 3150 & the 945 use the same Intel driver. Essentially, the 3150 is an "evolved" 945. So, as long as the system, including the LMCE bits, detects and configures for "intel" as the driver, there should be no problem, software-wise at least. Playback quality may be a different story.
It might help Intel users to initially install Ubuntu, rather than Kubuntu, and just install the Kubuntu pieces over Ubuntu. I had a similar issue trying to install other Ubuntu variants, and starting from a Ubuntu as a base install helped. I don't know how "touchy" LMCE gets about what's installed as a base system, though.
The SPA-3102 requiring manual installation/configuration actually is encouraging for Obi110 support. The devices are VERY similar, except for the extra Ethernet port on the SPA-3102, and the higher voltage requirements of the Obi110 (related to driving the ringer on the attached phone). As I said, the design team was made up of the same people (spun off, or quit?!?!, from Cisco/Linksys). If you can manually configure the SPA-3102, I'm sure similar settings can be used on the Obi. Plus, the Obi is cheaper and easier to configure for use with Google Voice as a free VOIP provider.
I don't have systems that can be modified to include a new video card. I have small footprint systems (2 Dell Studio Hybrids, and one ASUS EEE Box 202) as media directors. Those systems don't have room for a new video card. That means BUYing 3 new media directors, in addition to the 2 new machines I need to buy as lab machines for my RHCSA/RHCE studies (must be 64 bit systems, capable of hardware virtualization, 4GB ram min. each).
Those new machines can be repurposed as media directors when I'm done, to flesh out my system, fully as I originally intended. The NEW machines can have embedded nVidia, but I'm not replacing the older boxes that work perfectly well (well, maybe swapping the older/slower ones down to the kids, but not outright replacing them). Plus, all three current media directors have S/PIDIF optical out audio. It's not exactly easy to find small footprint, 64 bit quad core machines with embeded nVidia, S/PIDIF optical audio & support 4+GB RAM onboard, at least at a reasonable price.
Plus, the only system that I DO have with an nVidia card can't work with my Hauppauge cards (1600s), due to a (known) hardware conflict. Five new systems at an average $700 each is about $3500. It's not like I don't have the money for new ones, but with a wife & 2 kids, I've got way better things to spend it on... I can justify $1400-$1500 to the wife unit, conditioned on the fact I need the machines for my cert studies, and they can serve a dual purpose as media directors when I'm done.
My hardware was the reason I had left the LMCE community before... It's also why LinuxMCE hasn't exploded onto the scene ... Not trying to be insulting, or anything... I'm just saying.