Recomend budget / diy jigsaw drill please

Hi all
Don't use a jigsaw drill often but when I do, usually give up using it and resort to hand saw or circular saw (unless cutting a radius)

Have owned 2 jigsaws, both budget, aimed at diy and for occasional use, thought they should be ok but no. Current one is an Argos special, branded as 'Challenge'
Have used various blades, Bosch, Titan, Erbaur, various teeth, but the thing just wont cut. Always clamp on a straight edge as a guide but the blade wanders as cutting through the material. Had to enlarge a worktop cut out recently, standard laminate chipboard but one 960mm cut took ages and looked like I had chopped out with a machete. luckily covered by the sink and no-one sees it but I know its a dogs dinner

Don't really understand what makes a great jigsaw as in simplistic terms, isn't the thing just driving the blade up and down ? Obviously not as easy as that and must be loads more tech as you can buy a jigsaw for £20 or £400 +

I just want something for around £50, occasional diy use only, corded is fine, semi decent blade, and something that will cut through timber - am I expecting way too much for my budget ??

I own several Titan tools and to be honest, for my use I find them great and reliable. Yep I know no service or spare parts available buy hey, 2 year warranty and cheap enough to bin and replace when they bite the dust

Any thoughts on this model please.......Has favourable reviews ......many thanks

http://www.screwfix.com/p/titan-ttb285jsw-750w-jigsaw-240v/63333