lol.. i uses the pro 5 sling bag now, and the rest are just tamrac's modulars system.
the one striving point about tamrac bags is that the strap have this curve padding,
and it's sufficient enough the support the max weights that you can carry (eg: 6kg)..
and won't make ur neck, shoulder too stress after carrying for long. and 1 more considerable factor to consider is the price.. to each of his/her own for spending limits
for a large range of Tamrac bags, do check out K-13 Marketing, located @ 2nd floor of peninsular plaza (big yellow signboard). They have quite a range of products too, there you can compare which bag suits you best
Enjoys~ ;p