[ricky892]

Nikon D300 body, already have LB4, want to buy a 500mm Tele for bird shooting, budget must under $10000, now considering the followings:

1). AFS 300 F4 + TC17E, cost ~$10000 (best quality? but not convenient)
2). Tamron SP 200-500 F5-6.3, cost ~$7500 (less weight but no OS and HSM ...)
3). Sigma APO 50-500 F4-6.3 EX HSM, cost $7xxx (but no OS ....)
4). Sigma APO 150-500 F5-6.3 OS HSM, cost $7xxx (but not EX lens ....)

How about the quality of 2, 3, 4? Which one is better?
Difficult to make decision, C Hing pls help to choose.