I recommend these picks for guitar and mandolin.  They all perform well.

From left to right:

• Dunlop Prime Tone 1.0 mm  – My new favorite all around!  It wears like iron.  Seemingly last forever.  Slightly rough non-slip grip
• Snark 1.07 mm  – Great wear, pretty good tone, decent grip
• Dunlap Purple Tortex 1.14 mm – a good all around pick, will wear sooner than the picks on either side of it
• Dunlap Ultex 1.14 mm – another good pick, wears good, ok grip, decent sound