I was using 0.35 and 0.5 heads for a while, and finally found a 0.5 Slic3r configuration that was actually working for my TAZ3 (would love some defaults from Lulzbot though!)
Then suddenly the printer started acting up, with super low quality infills and wrapping all over. Same material same configuration. In order to be sure I switched to 0.35 head and used the default slic3r profile and I am still getting the same issue. Temperature does not seem to be the issue as extrusion seems to be going well on its own (outside a print).