Should I buy a carrycot for my 10 week old? Phil & Teds users, please help!!

[dazedandbamboozled]

Hi, I have an old Phil & Teds Explorer which I got secondhand. I have been using a carseat with it, and thought there was no carrycot that would fit it. Have just discovered that there is (there are adapters available that I didn't know about), but my daughter is 10 weeks old now! Having a dilemma about whether to get a snug carrycot or not as I've also stumbled across the face-to-face seat. Some sites say the carrycot will last baby til 6 months, and some say 8! Lots of sites suggest that babies don't use carrycots past 4 months anyway, but some disagree! Also, not sure what age range the face-to-face seat is suitable for. Now I know these other options are available, I'd like to get her out of the carseat because I always feel like she's too cramped in it. Just having trouble deciding which product to buy. Are there any guidelines on how long babies can sit in the face-to-face seat for? Given that my baby is now 10 weeks old, I'm not sure which product, the snug or the face-to-face, would be the most useful. Sorry for the long post, but I've been trying to figure this out all evening! Any advice/insights would be very much appreciated!