I think that there have been issues with ender tanks/chests and resets for a while (twilight forest was mentioned a lot in this), but I've never seen it personally. As I recall, there is a thrroughput limit to ender tanks, but nothing that you're likely to hit (go watch the DW20 S4 SMP lava age videos for reference, they had 6 pumps running full power and saw the limit, but feeding direct to a generator/small buffer shouldn't be an issue). Personally, as a starter system, ender tanks would be my choice, mainly for resource cost. Tesseracts require pretty much the entire set of TE machinery to craft (induction smelter for hardened glass, magma crucible and transposer), plus a diamond, 3 more ender pearls (which are tricky to get early, or 12 iron, which is useful), overall, they're what I make late game to overhaul my systems.