While it may be too late to beat the VAT rise, I'd add a vote for the Tamron 17-50. I got one just before Christmas and it hasn't really been off my camera since.

While its performance can't match that of my FA50 1.4 and Flektogon 35/2.4, I've found it to be pretty sharp, with decent bokeh for a zoom and certainly a worthwhile upgrade over the kit lens for the increased speed.

I think it depends on the type of shooting you do. For me, I have young kids so do a lot of available light shots that have to be composed quickly, so while I have got some nice shots with primes, my success rate is higher with the Tamron.

No, but I was bidding on it (too?). It went for just over £200 in the end, I think.

Thanks for the answers everyone - interesting to hear, as I have found both to be very good and have to look pretty hard to spot the difference between my FA50 1.4 and K50 1.4 (except that the K is much nice to focus manually) and have found all Pentax lenses I have tried to be pretty good (and continue to be amazed by the v2 kit lens for price)

I've been looking out for one of these for a while, as I have a Super Tak 135/2.5 with the 'inferior' optical formula, which I've been very pleased with. Any good tips on picking one up for a song?

I've got a moderate case of what, after lurking here for some time, I now know to be LBA. Over the past couple of years I have assembled and enjoyed using a small collection of old Pentax glass, mainly Takumars, K and M series lenses.

From what I've read, the K series currently seems better regarded than the M series, due to the perceived better build quality and better optics (in some cases).

I'm afraid I wasn't around when the M series was released - was it seen at the time as a retrograde step? It seems that some of the K series lenses, notably the 85/1.8, weren't really bettered until the A*/limited lenses.