In early 2002 I purchased a Phillips DSR 6000 from American Satellite, at a cost of only about $30 with shipping and tax. I was a new customer of DirecTv and if I stayed for a year, the TiVo would essentially be nearly free. Many retailers still offer deals such as these.
This was my second TiVo (first being a 35hr Series 1 machine I won in a TiVo contest in 2000), and my first time as a Directv user. I was instantly impressed at the picture quality of digital TV. Having owned a ~10 year old 27" mid-range television for the past few years, I never really thought I'd notice higher quality input but it was instantly apparent: the crystal clear picture was a definite improvement. Phillips has since replaced the DSR 6000 with a newer DSR 7000 model built on the Series 2 Tivo system, but the system served me well and I hear they are still in great demand on eBay due to their hackability (to get free directv, not just tivo hacking).
Directv and Tivo combined
I've since spent considerable time using Directv without a Tivo at the homes of friends and family and I must say that after trying it both ways, a Tivo is pretty much mandatory for satellite TV. I've often said that Tivo helps you "squeeze the shit of TV into a few diamonds" and when you're talking about a channel lineup that includes literally hundreds and hundreds of channels, it becomes very difficult to locate and watch your favorite shows. I went from a basic cable system of 50 channels to my ~300 or so on Directv and found that navigating the immense number of choices, and remembering what time to turn on each was daunting. A Tivo was perfect for grabbing a show no matter what channel or time it was on. After a few weeks of finding new favorites by word-of-mouth and a little surfing, the Tivo was filling up quickly and shows were only lasting a few days.
TiVo features, reliability, and upgrades
This model was very easy to upgrade, due to it being designed to handle two hard drives from the factory. After a few months of perfect operation, I sprang for a 80Gb prepared upgrade drive (a review of that is to come), cracked the case and installed it. With the expanded capacity I enjoyed longer shelf life for shows before their self-deletion and it wasn't until the unit was about six months old that problems arose. Reading the Tivo community site, it appears that reliability has been a common problem for the 6000, and on one hot (100 deg F/37 deg C) day the machine up and quit. The unit felt hot to the touch and I realized that airflow around the unit was more important than I thought.
After failed reboots and calls to customer service, the unit was shipped back to Directv and a refurbished replacement arrived shortly (I kept my 80Gb drive, they didn't say anything about the voided warranty). The replacement TiVo worked fine with the upgrade drive added, though for some reason the internal fan was very noisy. I suspect it was a return due to a lose ball bearing fan, and the Tivo Community again helped me find a cheap replacement fan that was more efficient and silent. I did my best to improve cooling around the unit to prevent a repeat of the previous failure.
A couple months passed before another problem cropped up as the factory hard drive encountered a problem that sent the Tivo into continuous reboots. The Tivo Community had similar threads on the problem, and they all pointed to hard drive errors. I did some diagnostics on the drive and figured it was time for a replacement. I purchased a 120Gb drive and ended up preparing it and copying the old data off the damaged drive. With the new drive setup my tivo was sporting 200Gb of space and all my saved shows were still there. Over time, about the only drawback of having so much capacity seemed to be that the Now Showing list would take a good 30 seconds to load, due to the slow processor and tons of data. Many shows were being saved for months on end and a full Tivo meant there were a good 150-250 entries.
Conclusion
Over the 18 months or so that I used the DirecTivo it served me well and I plan to go back to Directv from the cable system I'm on in my new home. To be honest, reliability was definitely a problem though I found ways of working around it. For that reason, I will probably spring for a new series 2 DirecTivo. Though I must say I'm hesitant to go with a series 2 directivo since DirecTv has crippled the USB ports and held off on the Home Media Option (with no definite plans to enable either anytime soon).
Directv with combined Tivo is a great system though, and I found it made the vast number of choices manageable.