Any of them will last a long time as long as you NEVER, EVER ride on anything but ice. I push mine to the lake and even that isn't really good for the studs. Either one will provide you with plenty of traction if you stud them properly. 1000 studs should be sufficient to do all three tires. Get 1", you want them to penetrate the carcass of the tire. The Cheng Shins are probably the harder compound of the two and will hold the studs a little better but the Trekkers aren't bad either.
John
1985 Eddie Sanders ATC330r
1986 Monstecate
1984 ATC70 (awaiting 125cc transplant)
1984 ATC125M
1986 GSXR 750 - Keepin' it old school!
1999 Arctic Cat 500 4x4 plow machine
1999 Arctic Cat Thundercat 1000 (lake lizard)
1996 Arctic Cat Jag 440 L/C (ditch banger)