Which do you post at and why?

I take it you mean for classified sales?

anyway – 1st class recorded signed for usually

First class recorded- I like to know its arrived.

Second class if lower value/dirt cheap/price has been haggled.

Yep for classified sales.

Seller discretion surly, I've never sent anything second class mind and often for parcels pay for special delivery.

whatever suits when i get there. usually standard parcels with added insurance…

unless its under a certain size as then it is the same price (or cheaper) to use special delivery 24hr.

i will ALWAYS insure if its worth over £30. Postage time is of secondary importance to me, its all about cover when it gets lost/damaged etc.

im fairly confident i've been had in the past by scallies claiming things haven't turned up…

As with tracknicko, it's all about the item getting there. I wouldn't fuss over 88p, but likewise if I'd asked for something of value to be sent I'd want it insured and tracked if it was of reasonable value. Of minimal value, first class if they told me they were in a rush.