Contact your DSL/fibre optic provider and see what their recommendations and/or requirements are... Without knowing exactly what their line encoding and tranmission protocols are, it's hard to make a further specific recommendation... There are at least two 2701HG variations, B and D...
Moreover, if by your post your indicating a future upgrade of the local physical network to fibre (to your house? or just the backbone?), I'd wait until it was functional and then buy a new router...
BTW, 20 yrs in the business, including 6yrs as an ISP owner/network engineer... trust me... it's good advice...
Simple....