If all you want to do is use it like a vcr, you don't need the subscription. You can tell it to manually record shows at certain times, just like your VCR. If you want to be able to fast forward through commercials on a show that you just sit down to watch, you would change to that channel, pause it for 5 or 10 minutes while you do other things (or press the record button). Then when you come back, you can fast forward.
However, the real advantage of tivo comes from the subscription. It then has access to all the tv listings. For example, I set up a season pass for the olympics with only a few steps. Now, every hour of the olympics are recorded, and it doesn't record the repeat show at 2am. To do it manually would be very time consuming.
My family has between 15 and 20 season passes. We have it recording news and political talk shows my dad and myself, old tv shows for my brother (MASH, I love Lucy, Cosby Show, Bonzana, etc), jeopardy for the whole family, etc. It took about 15 minutes to set up, and now whenever we turn on the tv, there is always something good on to watch. Especially for my brother's shows, he'd never know they were on, because they are on in the middle of night when he's asleep or the middle of the day when he's at school. If any of those shows change times or channels, tivo still gets them.
I'd suggest paying for it monthly for a month or two, and then decide if you want it.