Warwickshire 125 for 3 (Chopra 56*) beat Durham 122 for 7 (Housego 59*, Best 3-19) by seven wickets
Paul Best claimed 3 for 19 on only his second Friends Life t20 appearance to help Warwickshire to a comfortable seven-wicket success over Gloucestershire at Bristol.
The home side could post only 122 for 7 after winning the toss, Dan Housego top-scoring with an unbeaten 59 off 61 balls and left-arm spinner Best proving the most penetrating of the Warwickshire bowlers.
The result was never in serious doubt when the visitors replied as Varun Chopra (56 not out) and skipper Jim Troughton shared a second-wicket stand of 69 in 12 overs and victory was sealed with 11 balls to spare.
Muttiah Muralitharan was not surprisingly the pick of the home attack, conceding only 19 from his four overs - despite being hit for six by Chopra - and taking a wicket on a slow pitch that ensured scant entertainment.
Gloucestershire never recovered from a bad start to their innings. Benny Howell was run out for a duck after playing the second ball of the match to Best at point, who scored a direct hit at the bowler's end.
Housego was the only home player to adjust to a difficult pitch, accumulating his runs steadily before reaching his fifty with a six over midwicket off Jeetan Patel. By then he had faced 57 balls and struck three fours.
The next highest score was Ian Cockbain's 13 as the Warwickshire bowlers exerted a stranglehold, helped in no small measure by the lack of pace in the wicket.
Steffan Piolet, Chris Woakes and Keith Barker, who conceded 26 runs, all bowled economically in support of 21-year-old Best, whose victims were Alex Gidman, James Fuller and Ed Young.
Warwickshire lost Rikki Clarke for 9 to a brilliant boundary catch by Howell diving forward at deep square-leg off the bowling of James Fuller. But Chopra and Troughton were then able to bat without taking risks to put their side in a winning position.
By the time Troughton was caught and bowled by Muralitharan only 38 runs were needed in more than six overs.
Darren Maddy did not last long and was seen off by Ed Young, but Chopra continued his good form in the competition, reaching his fifty off 47 balls, with 4 fours and a six, and he struck thumped Fuller to the boundary to seal an ultimately comfortable win.