okay I'm getting back into shape again. I have been riding my giant sedona around town and trails for the past couple weeks religiously and keeping to a diet and all is going good. Only thing is that i am getting sick of the twist shifters on the bike. It is a 2005 model and in desperate need of some new shifters. I have a good knowledge of tuning and can fix just about anything but i have a question about shifters. I would like to replace them with a set of trigger shifters. I have come across a ton of different ones on the web. currently it has a 21 speed set up with the shimano megarange gear and altus deraileur on the rear. suntour cranks also. wondering what i can use to replace them. don't need high end stuff just stuff that won't break in a month. I plan on replacing all the cables also at the same time so any help with some part replacement numbers would be great. thanks.