I would like to buy a bike that will allow me to start learning urban jumping (from/on steps, curbs, manuals, riding backwards etc). Now, I know fixed dirt jump bike with alloy frame is one of best choice for this, but the problem is I would also like to do trial/commute sometimes too. Are there bikes that mixes these two activities? If not, is fixed dirt jump bike capable of being useful in commuting?

I was thinking about this bike: http://www.halfords.ie/webapp/wcs/st...Id_212589#tab2

It is supposed to be good mixture of durability and speed, but I know on regular mtb such this one, I will not be able to ride backwards on flat, also my movement will be restricted by bigger frame and wheels, also alluminum frame can snap on bigger jump. Is this bike good for starters?

I have also eye on http://www.ebay.ie/itm/Custom-Build-...item2a1e6414c0 , is it good bike for this price?