Re: tell me which to buy
Go find a welding supply shop. They'll be cheaper and can get you set up rather than a clerk who knows less than you do.
If you are going through Canadian Tire make sure you at least get a helmet and not the masks they include with their kits. But they're raping you on the helmuts, $50 for one that I might give $20 for, so I highly recommend going somewhere else.
Canadian tire has rebadged versions of the lincoln welders, and it looks like the Pack 10 is a 135 and the Pack 15 is a 175 (judging on voltages).
Don't forget that you'll want to get a bottle of gas instead of the flux core so you'll need the regulator and the correct wire (doesn't say in the description what wire it includes). Most farm supply shops have cylinders available