I done the same migrating from UKFSN to Be at the start of the year. Changeover was straightforward and was done in the middle of the night. Initially I signed up for the Unlimited upto 24mb package, but because I live far from the exchange could only get 4mb, I then regraded for free to the cheaper Value package. Still happy with 4mb on Be as I was previously on 1.9mb on UKFSN max.
Also, go via Quidco for an easy £40 cashback when you sign up.
No referrals.