Thanks Stuey, but I am not in the market for a 50mm. I already have several 50-55mm lens in my possession. Even on APS-C, I have found that there is a little bit of distortion when it comes to head and shoulders shots. It is a classic case of the rendition of a nifty.
Hence why I am looking at the short fast tele of around the 70-90mm Range.
The compression of the image by a short-tele lends itself better for portrait shoot. I know that there is an argument of the FOV of a 50 on APS-C provides the 35mm equiv of a 75mm, and that a 55mm is the equiv of about 83mm, but they are still a 50mm and 55mm.
My 50-135 is much better in this repsect, but it has two "issues"
One, it is a zoom, albeit a mighty zoom, and hence has the compromise of creating a zoom in the first place
Second, at F2.8 it does not often give you that shallow DOF that something faster would give you.
Having said that, it does not matter in the studio, as I normally shoot 1/125sec at F8 anyway. But it would be nice to reduce power and get shallow DOF.

However, it comes down to whether the 1/2 stop of the 70mm would provide more "magic" even though it is not compromised in it's optical quality by being a prime instead of a zoom.

Oh and of course, whether the SMC or HD version is better suited.

That is worth knowing. There is no rush at the moment. So I will keep an eye out. Thanks for this Robert.

Thanks all, it is a tough choice.

The SMC will provide nice starburst effect, which is good, yet because of the blades being straight, it has a fussier (for me) bokeh for portraits

The HD has better contrast wide open (which is good) and has better bokeh due to the rounded blades, but loses the starburst effect.

It will basically come down to what is more important for me.

Then again, Would it be so much better than my DA*50-135 for Portraits?
It would be better for travel/street as it is so much smaller than the 50-135

It is a tough decision I have to make really. And the question is what would it give me. (And if anyone says 77mm I will hate you as that is really the one, but I cannot afford it...... )

Horses for courses really.

If you are intending to shoot insects, then longer is better as you don't spook the insect. Shorter is better for fawna.
On the other hand, having a 35mm Macro is better for general use and shallow DOF where a normal 35mm or indeed a 50mm will only allow you to get within 1.5 feet of a subject
Then again having a longer focal length macro like the 90, 100 and 105, double up as superb portrait lenses.

Like I say horses for courses.

There are lots of permutations out there really.

Default choice would be the DFA-100mm F2.8 Macro WR. I don't have one but from I have seen it is an epic lens. Weather sealed too.

On the other hand, the Sigma 105mm F2.8 Macro is another stunner, and actually the default lens used by AP magazine for testing camera bodies. Why? it is the only one on all mounts, and again it is an epic lens.

Tamron 90mm F2.8 is another fantastic lens, and if you decide this is the one, get it while you can as Tamron have brought out a newer version with VR but not on the K-mount.

Second-hand.
Well I do have a couple of pre-owned Macro lenses, for a decent price.
The aformentioned Sigma 105mm but not DG spec, not that it matters.

And the second beauty:-

Tamron 90mm F2.5 SP Macro. Manual only, 1:2 ratio, but mine came with a 2x 1:1 converter, making it a 180mm F5 macro. Very slow to use (its a macro) but built like a tank and stunning in its sharpness. Cost? £120 with converter. Bargain really.

One thing though with this lens, ensure that you set the WB to anything other than Auto, as the camera can be fooled for some reason. Mind you if you set to daylight, cloudy, shade etc, no problem at all.

Worth looking for, and there are plenty about.

So, the Pentax DA70mm F2.4. A nice fastish portrait prime. But which would you choose to buy?
Secondhand, the SMC version is around the £360 mark. New, the HD version is £510. So £150 more.

Has anyone used both and would the HD version be worth the extra cost, especially as £150 could buy some nice photo accessories?

I agree, but I suppose he is trying to emulate the DA lenses.

The rest of the lens looks stunning though.

I have a few, it depends on where I am going or what I am taking

Lowepro Messenger 240
Lowepro Orion backpack
Lowepro Mini Trekker AW
Lowepro sling 250 AW
Town and country (aka Jessops) - The MF stays in the most of the time

Don't talk to me about Olan Mills.......Terrible set up, conveyor belt photography. We had a family portrait done there many years ago. Hateful place. Thank god it is no more in the UK.

AS for these back drops, I think I prefer going to Castlefield in Manchester and you are undercover due to the viaducts. It is real rather than fake.

Boy am I cynical at the moment.....

Like a lot of Photographic genres, it is difficult to define what street photography is.

For instance, Cartier-Bresson is the most well known "street" photographer, but how many were staged? David Bailey and Jean Shrimpton in Manhattan, Would they be considered Portraits, Fashion or street? Maybe all three.
Candids as you walk about? almost certainly. But if you have the gift of the gab and get someone to pose for a shot? Well certainly, but then again it could be considered a Portrait.
How about taking a shot of a building, yet have a person in it to give it perspective. Is that street or Architecture? It has a person (so street) but a building is the subject (Architecture).

At the end of the day, it comes down to this, If the whole shot involves aspects of roads, paths, buildings, man-made town or city parks and ultimately people in their day to day life, whether posed or not in the enviroment, would be considered street.

Like I say, the concept of Street is blurred.