Need some not-to-expensive tires for our base model 2010 Mini which came with Contipro Contact 175 65 R15.

The General Altimax RT43 gets much better reviews at Tire Rack. Anyone know any reason why I shouldn't get them, or anything else I should consider?

 

You are not limited to OEM 175/65-15 tire size.

I'd recommend considering 195/60-15 to give you more tires to choose from-
http://www.tirerack.com/tires/survey...wws=N&showcm=N

General Altimax RT 43 also comes in this size for $64 which is less than the size you mentioned.

The difference in tire sizes gives-
175/65-15 narrow tread has less rolling resistance and slightly better mpg for commuting, less weight (up to 3 lbs lighter than 195/60-15).
195/60-15 wide treads give more grip for handling, braking, accelerating. Good ride comfort depending on which tire used.

In Standard Touring All Season tire class-
http://www.tirerack.com/tires/survey...wws=N&showcm=N
Continental TrueContact $79 each
Tirerack test result-
http://www.tirerack.com/tires/tests/...y.jsp?ttid=189
However these tires are T speed rated which is less than the OEM H speed rated for the MINI. Some tire shops will not want to mount tires of less speed rating than what comes on the car from the factory. You can go up on speed rating but not down.