Yeah the fly attachement is pretty useless and will just get in the way when you want to use dumbbells

Surprisingly those benches aren't actually that bad, certainly not for a beginner anyway, and looking at Argos I can see why you're getting that one as it's cheaper than the one without the fly attachment
As an example, we got the Argos bench and stuck it outside and has easily coped with 150kg (me plus weights) and doesn't even creak or anything and feels pretty solid.
Don't bother with the chrome set, get the 50Kg cast-iron set instead for £60, and with the £20 saved buy the 2 x 10kg cast-iron plates instead would be my advice.
Not a bad set of weights then for £120 - obviously there are much bigger and better sets to be had, but then you are in the region of £100 plus for a bench alone!
*edit*
I would add, the best thing is to check your local free-ads or sites like gumtree, you can get a lot of weight for not much money, and it's not like you have to worry about quality.....it's just lumps of iron after all
