First, SLI is largely dying imo. It's extremely dependent on the game to implement it properly, so you wont get consistent performance across the board.
Second, the 2080ti is a beast, but I dunno if it's gonna get to 100+ FPS in all titles. It will, however, give a more consistent performance boost.
TLDR: Go for the 2080ti, but don't be surprised if some games still don't consistently stay over 100fps. That's what the G-Sync is for.
It is what it is.
ASRock Fatal1ty Z370 Gaming-ITX/ac
GTX-1080ti Founder's Edition
Samsung M.2 950 PRO
SanDisk Ultra II
Optimus V1 LGA-1151 Waterblock
Singularity Protium Pump Top/Case
EKWB 10x0 Waterblock
SavantPCs 240mm Reservoir
Windows 10 Pro
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