Gawain, I got FIOS about 5 months ago and have no major complaints on the day-to-day stuff. I had the lowest tier Comcast cable setup before with no complaints about that either. On typical net surfing I noticed no real change. When downloading larger files, my download speed with FIOS seemed about twice as fast as it was with Comcast - typically 350 kb/sec for Comcast vs 600+kb/sec for FIOS. I don't know if Comcast has upped its basic speed since I left their fold though.
Some comments from my experience:
1) They had to dig a trench in my yard from the street to the house. That was done quickly and cleanly. After several days you had to look closely to see exactly where they dug the trench. They did very nice work in restoring the yard.
2) Inside installation was less time than they stated (4-6 hours), but I found out later that they left out a few things...like telling me about the free router and how to adjust its settings. They didn't even tell me the password which was different than the documentation said it should be. I wrongly figured that maybe they don't want you to be playing with the router settings. Several weeks later I determined that they left my router in an unsecured state. I was rather pissed about that. A call to support allowed me to correct that "little" security hole very fast.
3) When I signed up you had a choice of an Verizon MSN software package or a Verizon Yahoo one. I went with the Yahoo version. It is okay but I did prefer the Comcast software suite and homepage. Comcast gave you McAfee security software while FIOS (Yahoo version at least) gives you CA (Computer Associates) softare. CA is alright but doing a full antivirus scan takes forever. McAfee could scan my entire system in about 45 minutes or less. CA antivirus takes over 2 hours. I used to run my full system scans over lunch but now I've had to schedule them in the middle of the night.
I was pretty happy with Comcast broadband before the switch. I got a good rate on FIOS ($35/month) but the main reason was that I wanted to free myself from Comcast as my TV provider and their broadband rates went up if you weren't a cable TV subscriber.
Well, I hope that helps you a little bit. If you have any specific questions, I'll be glad to answer those that I can.
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