My 'new' Langster is making some odd noises from the Bottom Bracket region so I'm going to swap it.

Does anyone know if either an old 105 square taper BB will fit,

or

if this is any good? I don't think it's what's in the original.

first you should tighten the nuts on the BB, then try all the chainring bolts. Lastly tighten your pedals and seat. Those are things that may make noise. If you just got the bike the bb is fine. Mine still ****ing clicks and i just kinda ignore it cause everything is tight

That's good thinking.

The BB makes a nasty sound even on the bike stand when the rear wheel is just turning over the chainset (I'm running it fixed), so I've just assuming it's knackered. From the reviews I've seen it won't be long before it really is knackered, so some preparation for the event can't hurt

The Shimano 105 BB is said to be 43.5mm, whereas the Sugino BB is 42mm. I suppose the extra 1.5mm will mess up the chain line.

cluelessgoon, on your Langster do you still have the original/stock cranks on it: Sugino RD2? If so, when paired with the stock BB (103mm), it will create a chainline of 45mm. If the Shimano BB is said to create a 43.5 chainline, it would seem that it would push your 1.5mm further out, creating a 46.5mm chainline.

HOWEVER, I suspect that if you move your chainring to the inside of the crank spider, it will create a 42mm chainline.
I suspect that this will occur, because it has been documented that the SUgino RD2 cranks, when paired with the recommended 103mm BB, will create a 45mm chainline. When mounting the chainring to the inside, it seems the move the chainline about 3mm, the thickness of the spider on the chainring and perhaps half the width of the chainring itself, creating a 41mm chainline. I haven't moved my chainring to the inside so I can't genuinely be sure of that. In (my) theory if you do use that Shimano BB, it would create a 42mm chainline.

If anyone can refute this to be truth I would love to know. The only part in which I am unsure of is, what chainline you will get, when the chainring is moved to the inner part of the cranks.

Wil - cheers for your detailed reply.
Initially I thought the creaking, knocking tapping sound was the bottom bracket, but after having stripped the bike down and tried a 105 bottom bracket with 105 cranks, it was exactly the same. Curiously I found that the 107mm 105 bottom bracket fit just fine and when I moved the ring to the inside of the cranks the noise became a lot worse. Inspecting the chain/freewheel it looks like this is just the chainline being off. I put the ring back on the outside and it worked great. I'm running the bike fixed mostly, and the noise is gone, so I guess it's either the chainline or the freewheel.
I rebuilt the bike using the original bits as the 105 cranks are 172.5 (supplied Sugino cranks are 170) which is great using gears but feels too long fixed. I measured the chainline like this at 47mm which surprised me. This is the original configuration I bought the bike in.
I think longer term I'll want to swap the current 42T/16T for something else as I can't spin that fast fixed or SS and blast up all hills no problem. Not sure if I should get a new chainring/chain or freewheel/fixed sprocket.