my initial experience of chip has been very positive.
(in my defence i was tired) i tried to open an isa, i was a new customer so was looking at 5.12% however by mistake i opened a savings account (still 5% which is nice but presumably not tax free). I noticed my error a day later - at which point i think i had passed the deadline for the boosted percentage rate, so i opened the isa anyway at 4.8% (i was no longer a new customer) and transferred the money from the savings account into the isa.
on the off chance i fired an email to their support asking if i could get the new customer boost anyway as i am an idiot and opened the wrong account, and they added it for me.
so all in all, i am pretty pleased at their support as they had my money anyway, so they had no incentive to give me the extra interest.