which artifacts?

Pathris

Got some credits to burn. Level 1 sip ring and +1 con, or just level 2 sip?

Sena

For PvP, level 2 sip ring. For bashing, probably level 1 in each (or +2 con), but it depends on your current con and level.

Pathris

I don't PvP, and my current con is 15 and level 85

Sena

Assuming you just sit in the room taking damage and sipping is your only form of healing, L2 sip ring would be best in longer fights (40+ seconds), +2 con would be better in shorter fights. Most other healing (boar, berkana, moss/potash, evoke vigour, forest harmony, etc.) scales with max health as well though, so with those, con is better. Con also helps more against burst damage (if something can kill you in 2-3 hits, a sip bonus likely won't matter much).