These ads are TRULY HORRIBLE in my opinion. Absolutely unacceptable, and they have made me seriously start looking at TiVo alternatives that I have always ignored. I have seen a lot of these pre-roll ads, and I am too disgusted for family-friendly words. I have never been interested in replacing my TiVos, but that has totally changed now, and I am certain I will never spend another cent with this company unless they turn this around! They have violated their implied contract with me, and they cannot be trusted.
Here is another BIG problem you will start to see with these ads: You can sometimes skip them before they start by hitting the jump forward button during that nasty BSC (but they seem to be trying to disable that). If you regularly try that, you will frequently see your TiVo lock up and then reboot after about a 30 second wait! The first clue that you have been screwed is a short error message that says "Can't play now. E117"; once you see that, it WILL eventually reboot.
BTW, the pre-roll commercials are absolutely NOT recorded with the show - if you stream a show from another box running TE3 (or copy it to a Series 3), the nasty ads are NOT seen. I have now totally quit watching ANYTHING directly on my one TE4 box for this very reason.