Currently, I use both FloBikes and NBCGold and enjoy them both. Some pros/cons, YMMV:
FloBikes (between $130-$150/yr):
PROS: Tons of cycling; almost too much to watch at times. Lots of cyclocross and track cycling in the fall/winter, Belgian classics (including some less well-known races), the Giro, most Worldtour races (except ASO). English commentary is good (often Rob Hatch/Rob Hayles). App is easy to use across multiple platforms (I view on my IPhone and utilize Amazon Firestick to watch at home). Lots of race replays to watch. Reasonable price for all the coverage. They have some interesting/intriguing behind the scenes type documentaries.
CONS: Cyclocross commentary is sometimes lacking, but has improved greatly this year (now have native English commentary; usually Anthony McCrossen or FloBikes commentary out of Austin, TX). So, you may be watching an odd race with no commentary. I've experienced some issues with audio/video syncing but not often and probably a result of the feed they are receiving.
NBC Gold (~$60/yr):
PROS: TdF and Vuelta (my favorite GT). Also have Paris-Roubaix and Liege-Bastogne-Liege and other ASO races. Decent track program and major cyclocross races. Good commentary; either Phil Liggett and his lackeys (I'm not a fan of CVV, Bob Roll or Chris Horner; they are all annoying IMO) on the "commercial" feed or Matthew Keenan/Robbie McEwen on the "ad-free feed".
CONS: The commercials on the "main/commercial" feed are becoming a distraction to the point of really disrupting the flow of the broadcast. Fortunately, the ad-free feed is fantastic and MK/RM have great rapport. Only get ASO races and major track/cyclocross races. Huge gaps between these events where there is no coverage.
If I had to pick only one, it would be FloBikes due to more races/content to watch. But, currently I'm happy using both and justify the expense because in a typical cycling season I have at least a couple of races to watch each week.