If you get a Hauppage HD-PVR then you can capture the HD output of a STB. DTA's only have a coax output, and only output SD for old TVs. Otherwise you will be limited to capturing SD only with analog tuners. Since the HD-PVR is an external USB device then you don't have to worry about low-profile. You will want to use the IR-blaster(s) that comes with your standard MCE remote receiver. The one built into the HD-PVR can be problematic. The only bad thing is the HD-PVR is a little pricey running at about $175 per tuner... but they fill a very needed niche for HD capturing from a STB (whether that be cable or satellite, or fiber).
If you are fine with SD only, then I'd say you could get a few analog tuners really cheap on Ebay.
I'm not sure on specific models that would be low-profile or that come with the ability to control their own IR-Blasters (I've got an old analog Hauppauge PVR-150 that has an external port to plug in the blaster.) Then again, you could always go with external USB analog tuners to not have to worry about it.