Judging by my experience stay well away from the cheaper Eastern made variety you get in the big stores anyway Frank. Very very poor value no matter how little you pay for them. Maybe the better iroko items are OK, but go with caution.
Luckily we paid very little (near to end of season), but the wood is soft, fungus and split prone rubbish (not sure what it is, a reddish non local something or other which when new looked like it might have been something a bit more respectable), there's no even slightly waterproof finish (only a stain), and the glue used to joint the wood to make the blanks is not waterproof.
They got rained on a few times, but nothing major. We'll be lucky to get another season out of them unless a good soaking in Danish oil will stabilise the situation.
I've just spent an afternoon and a bottle of chair doctor glue fixing 5 chairs and a table - almost every small clamp i have is in use (5 - 6 per chair)