Hi, make sure its the USD version, sometimes people mix them up with non USD version (which also cost around 500 2nd hand)
sony has 2 300telezoom, the SAL75300 (which is terrible imho) and the SAL70300G (which is seriously a killer lens, except for during lowlight)
and yes, the tamron70300USD is a good lens and a very good investment if you need a 300mm reach.
doesnt matter not aipo to me most drybox are the same, as long it has a digital controller that can auto shut off or on... i prefer those with auto type, turn off when it reach too dry, turn back on when its wet.
the only problem with china non branded (simply randomly pick a brand and chop there with no physical existing warehouse in china), so called with 1 year warranty, they end up telling you need send back china need wait 1-2 months...if i recall,
lwliam was one of the victim, and switch to aipo? let him tell his story and aipo honors their 5 years warranty with no question asked. well u pay a little more for a good service. (dont scold me fanboy yea, im just stating the obvious, i believe there are many ppl already got victimized by china drybox after sale service.... ask any aipo user, u wont get negative feedback)